Location of the "Cooling fan switch"
- Thread starter azmattaz06
- Start date
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azmattaz06
New Member
I have a 94, Automatic 3.2.. Os that any better? i believe when i turned on the AC both fan's were on so im starting to think it is that sensor but i got like three people saying the one im showing is the right one to change and like some other people saying it's not.. That's where im confused..
Mr Anonymous
Tire Wall
Who said not to change the ECT sensor?
Trust me, that's the part you want to replace. The fact that your fans come on with the auto climate control shows that the PCM, CCRM, and fans themselves are working, the ECT sensor is the last component.
Trust me, that's the part you want to replace. The fact that your fans come on with the auto climate control shows that the PCM, CCRM, and fans themselves are working, the ECT sensor is the last component.
Well if that's true then someone has bastardized the fan wiring seeing as the power source is wired in parallel.
The cooling fan system is controlled during vehicle operation by the CCRM and PCM which will energize the radiator electric motor under the following conditions:
Radiator electric motor is turned on with reduced current for the 3.0L SHO and on at low speed for 3.0L, 3.2L SHO and 3.8L if:
a. Engine temperature is higher than normal. Radiator electric motor starts running at 102°C (215°F) and stops running at 99°C (210°F).
b. A/C clutch is engaged.
Cooling fan will run at high speed if:
a. Engine temperature is higher than desirable and radiator electric motor has been operating at low speed. Radiator electric motor starts running at high speed at 110°C (230°F) and stops running at 107°C (224°F).
On 3.2L SHO engines, low speed radiator electric motor operation is achieved by using a dropping resistor in series with the motors.
The 3.0L/3.0L FF, 3.0L SHO and 3.8L use a dual winding radiator electric motor in which low speed fan control is achieved through the low fan control winding circuit (no dropping resistor).
The normal operation and cycling of the radiator electric motor causes the temperature gauge indicator to read between the mid-point and upper portion of the temperature gauge scale.
The slightly higher indicator reading returns to mid-point when radiator electric motor operation begins.
For the '93..............
The cooling fan is controlled during vehicle operation by the Constant Control Relay Module (CCRM) 12B577 and Powertrain Control Module (PCM) 12A650 which will energize the cooling fan under the following conditions:
Cooling fan is turned on for the 3.0L SHO and on at low speed for 3.0L, 3.2L SHO and 3.8L if:
a. Engine temperature is higher than normal. (Fan starts running at 102°C (215°F) and stops running at 99°C (210°F).
b. A/C is on and vehicle speed does not provide enough natural airflow. (Fan starts running at speeds at or below 69 km/h (43 mph) and stops running at 77 km/h (48 mph).
On 3.0L and 3.2L SHO engines with ATX, low speed cooling fan motor operation is achieved by using a dropping resistor in series with the motor/motors.
Normal operation and cycling of the engine cooling fan will cause the temperature gauge indicator to read between the mid-point and upper portion of the temperature gauge scale. The slightly higher indicator reading will return to mid-point when fan operation begins.
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Storm-Chaser
New Member
Ah, no . . . . it's not.
First of all, what indication is there that the fan should be on ? In the absence of having a mechnical water temperature gauge, or having verified the operation of both the Gauge Temperature Sending unit and the instrument cluster TEMP gauge are both operating correctly, there is no accurate way of determining when the fans should cycle-on, cycle-off, or cycle between Low-speed and High-speed operation.
IF the Gauge Temperature Sending unit is not sending accurate information to the TEMP gauge on the instrument cluster, then there's no direct or indirect way to determine if and when the fan/fans should be cycling on.
The same is true if the TEMP gauge on the instrument cluster is not displaying temperature correctly.
Second, using the A/C to determine that the PCM is operating correctly, only verifies that engaging the A/C is resulting in the PCM signaling the CCRM to activating the fan relays and that they and the fan/fans are operating correctly. It does not verify that the PCM is correctly interpreting the information being provided by the Engine Coolant Temperature Sensor (ECT).
Third, it also fails to take into account that azmattaz06 may have the wrong CCRM for his model-year ATX application. It has been repeatedly shown here, that having the wrong CCRM can result in the fan/fans not operating correctly.
Furthermore, a malfunctioning ECT often results in other issues, as the PCM also uses coolant temperature information in metering fuel to the cylinders, which affects air-fuel ratio, that in turn affects how well the engine runs (ie. acceleration, fuel economy, etc.). Yet there's been no mention of the car running, accelerating poorly, or getting poor fuel economy.
First of all, what indication is there that the fan should be on ? In the absence of having a mechnical water temperature gauge, or having verified the operation of both the Gauge Temperature Sending unit and the instrument cluster TEMP gauge are both operating correctly, there is no accurate way of determining when the fans should cycle-on, cycle-off, or cycle between Low-speed and High-speed operation.
IF the Gauge Temperature Sending unit is not sending accurate information to the TEMP gauge on the instrument cluster, then there's no direct or indirect way to determine if and when the fan/fans should be cycling on.
The same is true if the TEMP gauge on the instrument cluster is not displaying temperature correctly.
Second, using the A/C to determine that the PCM is operating correctly, only verifies that engaging the A/C is resulting in the PCM signaling the CCRM to activating the fan relays and that they and the fan/fans are operating correctly. It does not verify that the PCM is correctly interpreting the information being provided by the Engine Coolant Temperature Sensor (ECT).
Third, it also fails to take into account that azmattaz06 may have the wrong CCRM for his model-year ATX application. It has been repeatedly shown here, that having the wrong CCRM can result in the fan/fans not operating correctly.
Furthermore, a malfunctioning ECT often results in other issues, as the PCM also uses coolant temperature information in metering fuel to the cylinders, which affects air-fuel ratio, that in turn affects how well the engine runs (ie. acceleration, fuel economy, etc.). Yet there's been no mention of the car running, accelerating poorly, or getting poor fuel economy.
Storm-Chaser
New Member
The reason I ask, is that the ATX uses two cooling fans, triggered by two separate relays in the CCRM. Thus [you] need to verify that both fans operate correctly, not just that "a fan comes on when . . . . ".
When the A/C is engaged both fans are actuated continuously and do not cycle on/off with the A/C clutch. Thus it is one of two ways to determine if the both fans operate. The second is to simply provide a 12-volt power source to each fan and see if both actuate and run.
Of the two fan relays, the Low-speed Fan Control relay is activated by the CCRM when the PCM determines that the engine temperature is higher than "normal". The PCM signals the CCRM to energize the relays. The Low-speed Fan Control relay activates the fans at low-speed when engine temperature reaches 215° F (102° C) and deactivates the fans when engine temperature drops to 210° F (99° C) (if the A/C is not on).
If the PCM determines that the engine temperature is higher than "desired", the High-speed Fan Control relay activates the fans at high-speed when engine temperature reaches 230° F (110° C) and deactivates the high-speed (fans step-down to low-speed) when engine temperature drops to 224° F (107° C).
Normal operation and activation of the radiator fan/fans should result in the temperature gauge indication reading between mid-point and the upper portion of the temperature scale range (provided the "TEMP" gauge is operating properly).
Thus in the absence of any accurate temperature information, it's difficult to draw any association between what is displayed on the temperature "gauge" on the instrument cluster and exactly when/whether the fans come on. At best you can only make generalizations.
The ECT is a thermistor-type sensor - a thermally triggered resistor. As engine coolant temperature increases, the resistive voltage output of the ECT decreases. It has a range of 5.0V to 0.0V; voltage resistance values are 0.59 volts at 195° F (90.5° C), 0.50 volts at 206° F (96.7° C), and 0.40 volts at 221° F (105° C). I did not find a voltage value for temperatures at or near 230° F (110° C). Thus problems in the wiring harness between the ECT and the PCM could also be a problem source, given the relatively small resistance value changes between 195° F (90.5° C) and 221° F (105° C). That's 0.18 voltage differential across a 25° F temperature change (0.59 volts and 0.40 volts, respectively).
When the A/C is engaged both fans are actuated continuously and do not cycle on/off with the A/C clutch. Thus it is one of two ways to determine if the both fans operate. The second is to simply provide a 12-volt power source to each fan and see if both actuate and run.
Of the two fan relays, the Low-speed Fan Control relay is activated by the CCRM when the PCM determines that the engine temperature is higher than "normal". The PCM signals the CCRM to energize the relays. The Low-speed Fan Control relay activates the fans at low-speed when engine temperature reaches 215° F (102° C) and deactivates the fans when engine temperature drops to 210° F (99° C) (if the A/C is not on).
If the PCM determines that the engine temperature is higher than "desired", the High-speed Fan Control relay activates the fans at high-speed when engine temperature reaches 230° F (110° C) and deactivates the high-speed (fans step-down to low-speed) when engine temperature drops to 224° F (107° C).
Here is a thermal time-line on when the fans should operate as a function of engine coolant temperature:
Off < 210° F (99° C) | Low-speed | 215° F (102° C) > On | Off < 224° F (107° C) | High-speed | 230° F (110° C) > On.
Off < 210° F (99° C) | Low-speed | 215° F (102° C) > On | Off < 224° F (107° C) | High-speed | 230° F (110° C) > On.
Normal operation and activation of the radiator fan/fans should result in the temperature gauge indication reading between mid-point and the upper portion of the temperature scale range (provided the "TEMP" gauge is operating properly).
Thus in the absence of any accurate temperature information, it's difficult to draw any association between what is displayed on the temperature "gauge" on the instrument cluster and exactly when/whether the fans come on. At best you can only make generalizations.
The ECT is a thermistor-type sensor - a thermally triggered resistor. As engine coolant temperature increases, the resistive voltage output of the ECT decreases. It has a range of 5.0V to 0.0V; voltage resistance values are 0.59 volts at 195° F (90.5° C), 0.50 volts at 206° F (96.7° C), and 0.40 volts at 221° F (105° C). I did not find a voltage value for temperatures at or near 230° F (110° C). Thus problems in the wiring harness between the ECT and the PCM could also be a problem source, given the relatively small resistance value changes between 195° F (90.5° C) and 221° F (105° C). That's 0.18 voltage differential across a 25° F temperature change (0.59 volts and 0.40 volts, respectively).
I checked my service manual tonight, and it shows the 2 fans wired in parallel, which would make it operate just as SHOZ123 described it. Apparently, mine are "non-standard" in operation. I'm sorry for the confusion, azmattaz06.
Mr Anonymous
Tire Wall
Ok, let's try to simplify this for normal people with common sense in an absurdly complicated way...
Let's start by looking at the OP's initial post:
First, he states that the car has started to overheat at idle. Now, seeing that he is from Tucson, he's probably still seeing outdoor temperatures in the 50 to 70 degree range so overheating at idle can occur rather quickly. Starting a cold car in 60 degree weather should result in the fans coming on in about 10-12 minutes or so of idling -- you don't need any fancy diagnostic tools to determine this, it's just something that anyone familiar with these cars knows from experience. Further, being from that part of the country, he is probably familiar with the symptoms of an overheating engine. Sure, he doesn't describe the extensive diagnostic procedures he followed to come to this conclusion, but often a temperature gauge above the normal range and coolant boiling over are all you need to know (I know, I know, but the service manual didn't say so!).
Second, now let's see, he refers to the "fan's" (forgiving his innocent punctuation error) in the plural, so it's reasonable to deduce that he's driving a car equipped with an automatic transaxle since only those such cars were equipped with a dual-fan setup. Again, this isn't necessarily critical information, as the totality of his symptoms and description render the point more or less moot.
Third, his uncle, who has probably never worked on a SHO in his life but obviously has a keener sense of common sense than someone with their head buried in a service manual, came pretty close in his suggestion that a failed "cooling fan switch" was to blame. While he may not be up on his ASE vernacular, he obviously has actually been under the hood of a car and not just spent his life memorizing a service manual.
Fourth, he stated that the fans "do [come on] with the AC". Again, for anyone with an ounce of real world familiarity with these cars, this is a clear sign that the PCM is functioning properly as it is able to command the fans on; that the power relay in the CCRM is functioning since it is able to power the fans; and the fact that the fans are turning indicates that the fan motors themselves are functioning properly. Common sense dictates that the ECT sensor has likely failed, since this behavior began "recently" and thus unexpectedly, and the gauge sender indicates an unusually high temperature. While certainly not impossible, the likelihood of simultaneous ECT sensor and gauge sender failure is unlikely, so in this set of circumstances it is again reasonable to conclude that the gauge showing temperatures above normal is likely accurate.
Unfortunately, instead of just letting the OP solve his problem quickly by helping him identify the correct ECT sensor, it's location, and eventually how to change it, someone had to pipe up with completely superfluous nonsense about CCRM letter codes to completely muddy the waters -- as is his penchant to do, and then of course exacerbate things further with more useless trivia that has zero bearing on the current state of the OP's issue.
Let's illustrate absurdity by being absurd just a bit further...
Let's suppose instead that the OP posted asking what to do about a flat tire.
Most people would advise him to change over to the spare and see about having the flat repaired.
But, there will always be that one person who needs to correct and admonish everyone else, and go on to explain the chemical composition of rubber, how the tire was manufactured, what the correct tire pressure is, and lengthy procedures requiring lots of fancy equipment to determine why the tire failed. The big ass nail sticking out of the tread is not nearly a simple enough common sense conclusion... That about sums it up... :shakehead
Let's start by looking at the OP's initial post:
Sure, the new member and first time poster didn't provide a detailed resume and specific description of his car, but he's new so we'll cut him some slack and actually try to help him solve his problem instead of incessantly complicating and confusing the issue. Now, since he is posting in the V6 section, it's probably a good bet that he owns a V6 car. He's describing a cooling system problem, and while there are slight differences between the ATX and MTX cars, as well as some differences between years, the core system is essentially the same regardless so we'll just read his entire post and take the totality of the information he's provided and see if we can help or if that additional information is critical to helping him solve his problem.
First, he states that the car has started to overheat at idle. Now, seeing that he is from Tucson, he's probably still seeing outdoor temperatures in the 50 to 70 degree range so overheating at idle can occur rather quickly. Starting a cold car in 60 degree weather should result in the fans coming on in about 10-12 minutes or so of idling -- you don't need any fancy diagnostic tools to determine this, it's just something that anyone familiar with these cars knows from experience. Further, being from that part of the country, he is probably familiar with the symptoms of an overheating engine. Sure, he doesn't describe the extensive diagnostic procedures he followed to come to this conclusion, but often a temperature gauge above the normal range and coolant boiling over are all you need to know (I know, I know, but the service manual didn't say so!).
Second, now let's see, he refers to the "fan's" (forgiving his innocent punctuation error) in the plural, so it's reasonable to deduce that he's driving a car equipped with an automatic transaxle since only those such cars were equipped with a dual-fan setup. Again, this isn't necessarily critical information, as the totality of his symptoms and description render the point more or less moot.
Third, his uncle, who has probably never worked on a SHO in his life but obviously has a keener sense of common sense than someone with their head buried in a service manual, came pretty close in his suggestion that a failed "cooling fan switch" was to blame. While he may not be up on his ASE vernacular, he obviously has actually been under the hood of a car and not just spent his life memorizing a service manual.
Fourth, he stated that the fans "do [come on] with the AC". Again, for anyone with an ounce of real world familiarity with these cars, this is a clear sign that the PCM is functioning properly as it is able to command the fans on; that the power relay in the CCRM is functioning since it is able to power the fans; and the fact that the fans are turning indicates that the fan motors themselves are functioning properly. Common sense dictates that the ECT sensor has likely failed, since this behavior began "recently" and thus unexpectedly, and the gauge sender indicates an unusually high temperature. While certainly not impossible, the likelihood of simultaneous ECT sensor and gauge sender failure is unlikely, so in this set of circumstances it is again reasonable to conclude that the gauge showing temperatures above normal is likely accurate.
Unfortunately, instead of just letting the OP solve his problem quickly by helping him identify the correct ECT sensor, it's location, and eventually how to change it, someone had to pipe up with completely superfluous nonsense about CCRM letter codes to completely muddy the waters -- as is his penchant to do, and then of course exacerbate things further with more useless trivia that has zero bearing on the current state of the OP's issue.
Let's illustrate absurdity by being absurd just a bit further...
Let's suppose instead that the OP posted asking what to do about a flat tire.
Most people would advise him to change over to the spare and see about having the flat repaired.
But, there will always be that one person who needs to correct and admonish everyone else, and go on to explain the chemical composition of rubber, how the tire was manufactured, what the correct tire pressure is, and lengthy procedures requiring lots of fancy equipment to determine why the tire failed. The big ass nail sticking out of the tread is not nearly a simple enough common sense conclusion... That about sums it up... :shakehead
azmattaz06
New Member
Just to throw it out there my uncle is ASE Certified and his son own's a 92 SHO which by the way he has done lot's of work on and i have never seen him burry his head in a manual he has been working on car's since before i was born and is a damn good machanic. Anyway Thank's for clearing that up for me and just so everyone is happy i own a 94 Taurus Sho Automatic if anyone asked i could have provided any information needed.. But thank's anyway
Just to clear this up there are two fan relays. One high speed which allows full voltage to both fans and on low speed relay which runs the voltage through a dropping resistor (in the case of the ATX) and the provides a lower voltage to both fans.
At no time should just one fan be running. When this happens the cooling effect of the one operating fan is reduced considerably as it will actually pull air from the engine bay backward through the radiator on the side the fan is not running when at slow speeds.
Storm-Chaser
New Member
First, I figured he was asking about a Gen I or Gen II since he posted in the V6 forum, and figured it was an ATX since he stated the fans weren't coming-on. This meant the SHO was a '93, '94, or, '95, which are basically the same. But asked for verification (as well as the CCRM type) to ensure the wrong CCRM hadn't been installed by the previous owner - as we all know that *never* happens 
Second, the entire premise that the car is "overheating" has been based on the TEMP gauge reading in the upper temperature range without the fans kicking on. There were no other statements that the car was physically overheating, even after questions by Ishodu and itwonder. It could be that the gauge or gauge sending unit are at fault, which would be two of multiple possible faults to be eliminated before simply throwing money at the problem until it goes away. Most tests are simple and usually cost nothing to perform.
Third, there was never any information provided that the car was boiling over, nor any reply to the question on possible system leaks.
Fourth, you do realize that it does get cold, even in the desert during the winter, don't you?
Fifth, I've had several cars (including other Taurus's and SHOs) that could idle in 60°-70° weather and not cycle-on the fan (I'm using the singular term here in a generic sense).
Sixth, the fact that the PCM does "command" the fan/fans on when the A/C is engaged does not mean that the PCM is correctly interpreting the voltage value being sent to the PCM by the ECT, which is what initiates the entire process. These are two separate functions within the PCM.
Fortunately, I usually try to read through the entire thread up to that point, instead of jumping to conclusions and then throwing out rude, obnoxious, and condesending comments at other forum members. I like to be thorough, to ensure the other forum member fully understands the problem and doesn't end-up throwing money at a problem because I assumed something, for example like having the wrong CCRM or a bad TEMP gauge. But that's just me.
Second, the entire premise that the car is "overheating" has been based on the TEMP gauge reading in the upper temperature range without the fans kicking on. There were no other statements that the car was physically overheating, even after questions by Ishodu and itwonder. It could be that the gauge or gauge sending unit are at fault, which would be two of multiple possible faults to be eliminated before simply throwing money at the problem until it goes away. Most tests are simple and usually cost nothing to perform.
Third, there was never any information provided that the car was boiling over, nor any reply to the question on possible system leaks.
Fourth, you do realize that it does get cold, even in the desert during the winter, don't you?
Fifth, I've had several cars (including other Taurus's and SHOs) that could idle in 60°-70° weather and not cycle-on the fan (I'm using the singular term here in a generic sense).
Sixth, the fact that the PCM does "command" the fan/fans on when the A/C is engaged does not mean that the PCM is correctly interpreting the voltage value being sent to the PCM by the ECT, which is what initiates the entire process. These are two separate functions within the PCM.
Fortunately, I usually try to read through the entire thread up to that point, instead of jumping to conclusions and then throwing out rude, obnoxious, and condesending comments at other forum members. I like to be thorough, to ensure the other forum member fully understands the problem and doesn't end-up throwing money at a problem because I assumed something, for example like having the wrong CCRM or a bad TEMP gauge. But that's just me.
Storm-Chaser
New Member
Paul - that's what I said.
Maybe this would have been a better way to illustrate how the two fan relays work together:
Maybe this would have been a better way to illustrate how the two fan relays work together:
Here is a thermal time-line on when the fans should cycle-on/-off as a function of increasing and decreasing engine coolant temperature:
Increasing coolant temperature
Low-speed relay On > 215° F (102° C) | High-speed relay On > 230° F (110° C)
Decreasing coolant temperature
Low-speed relay Off < 210° F (99° C) | High-speed relay Off < 224° F (107° C)
Increasing coolant temperature
Low-speed relay On > 215° F (102° C) | High-speed relay On > 230° F (110° C)
Decreasing coolant temperature
Low-speed relay Off < 210° F (99° C) | High-speed relay Off < 224° F (107° C)
Bizzy
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azmattaz06, any updates for us as to the outcome?
azmattaz06
New Member
Engine and Heating Any idea?
Ok so i changed my ECT Sensor last night and after word's i let my engine hear up and it went to about the "N" and then the fan's turned on then today i drove and it went almost past the n with no sign's of slowing down but i had already arrived where i was heading to see what would happen.. Shouldn't the fan's have came on by then? One more thing just a little while ago im driving in my car for about 5 minute's and i had the heater on and all the sudden the guage starts going up to the N and it's about to pass it and the it drops really quick to about the M or A what could that have been? thermostat? or what? i also needed to add a bit more water because i let some drain out before i changed the ECT could that little bit of water make that happen?
p.s. What's "PSP switch/circuit open" ? that code came up and i have no idea what it is.. Thank's
Ok so i changed my ECT Sensor last night and after word's i let my engine hear up and it went to about the "N" and then the fan's turned on then today i drove and it went almost past the n with no sign's of slowing down but i had already arrived where i was heading to see what would happen.. Shouldn't the fan's have came on by then? One more thing just a little while ago im driving in my car for about 5 minute's and i had the heater on and all the sudden the guage starts going up to the N and it's about to pass it and the it drops really quick to about the M or A what could that have been? thermostat? or what? i also needed to add a bit more water because i let some drain out before i changed the ECT could that little bit of water make that happen?
p.s. What's "PSP switch/circuit open" ? that code came up and i have no idea what it is.. Thank's
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Mr Anonymous
Tire Wall
Chances are after changing your ECT sensor you had/have some air trapped in the cooling system as a result of breaching the system. Usually it will work itself out over a couple of heat-up/cool-down cycles, but you can also help it along by "burping" the cooling system.
azmattaz06
New Member
And how would i do that? sorry for all the question's but to be honest im only 21 and i know a bit but im trying to learn more so i appreciate all the help.
Mr Anonymous
Tire Wall
You want to begin with a cold engine and your car on a reasonably level surface (a slight incline is better than a decline).
Open the hood, place a catch pan under the car in the area under the radiator cap, and remove the radiator cap. If the coolant level in the radiator neck isn't at the top, fill it until it is.
Start the car with the climate control turned off, and let the car warm up. During this process you'll want to periodically check the temp gauge and shut the car off if the temperature goes above the "N" at all, and this will also help you get an idea as to where on the gauge the fans will normally kick on (should be somewhere between the "N" and "O" on the gauge). Depending on the amount of trapped air, you may need to top off the filler neck a couple of times as the car warms up.
As the car warms up, you may see small air bubbles in the coolant. Once the t-stat opens, you should get a nice little "burp" of air (obviously, don't be staring down the filler neck!). After that burp, top off the coolant in the filler neck, install the radiator cap, and top off your coolant reservoir to the "hot" fill level. (Note that you may not need to top off the radiator, and could have coolant start overflowing the filler neck once the air is purged -- just put the cap on and top off the reservoir.)
If your car has an OE-style thermostat with a "jiggle" valve, you may see a more steady stream of air bubbles at the beginning, and little or no distinct "burp" once the t-stat opens. Once the t-stat opens (the upper hose will get hot), you can squeeze the hose at its highest point a few times to help purge any remaining air. Obviously be careful of the temp of the upper hose, you should wear a set of gloves.
Once that's all done, just let the car run for a little while and monitor the temp gauge and fan operation for a couple of fan cycles. With the climate control off, the gauge should get up to about the "NO" range before the fans kick on, and the temp should drop to about the "MA" range before the fans turn off. With the climate control on, the temp should remain much steadier, usually in the "AL" range.
Open the hood, place a catch pan under the car in the area under the radiator cap, and remove the radiator cap. If the coolant level in the radiator neck isn't at the top, fill it until it is.
Start the car with the climate control turned off, and let the car warm up. During this process you'll want to periodically check the temp gauge and shut the car off if the temperature goes above the "N" at all, and this will also help you get an idea as to where on the gauge the fans will normally kick on (should be somewhere between the "N" and "O" on the gauge). Depending on the amount of trapped air, you may need to top off the filler neck a couple of times as the car warms up.
As the car warms up, you may see small air bubbles in the coolant. Once the t-stat opens, you should get a nice little "burp" of air (obviously, don't be staring down the filler neck!). After that burp, top off the coolant in the filler neck, install the radiator cap, and top off your coolant reservoir to the "hot" fill level. (Note that you may not need to top off the radiator, and could have coolant start overflowing the filler neck once the air is purged -- just put the cap on and top off the reservoir.)
If your car has an OE-style thermostat with a "jiggle" valve, you may see a more steady stream of air bubbles at the beginning, and little or no distinct "burp" once the t-stat opens. Once the t-stat opens (the upper hose will get hot), you can squeeze the hose at its highest point a few times to help purge any remaining air. Obviously be careful of the temp of the upper hose, you should wear a set of gloves.
Once that's all done, just let the car run for a little while and monitor the temp gauge and fan operation for a couple of fan cycles. With the climate control off, the gauge should get up to about the "NO" range before the fans kick on, and the temp should drop to about the "MA" range before the fans turn off. With the climate control on, the temp should remain much steadier, usually in the "AL" range.
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Storm-Chaser
New Member
It helps to post the ODB code and code type. For example, code 52, "O" or (KOEO).
If the code you got was a code 52 during the KOER test, it means you probably didn't turn the wheel far or long enough during the power steering pressure switch test.
Assuming that everything else is working correctly, there may be air in the cooling system, and the highest point in the system is around the throttle body/Idle Air Bypass intake plate. Do separate searches using the term "burp" and "burping" and you will find a number of tehcniques on how to do this. Probably the easiest way to burp the coolant system, is by removing a throttle body coolant line. And realize by saying easiest, I mean the easiest way to get the air out of the system, but for some not the easiest technique to do.
The Service Manual procedure does not completely bleed or "burp" the cooling system in the SHO like it does in the non-SHO because of the position of the throttle body, relative to the rest of the cooling system.
From a cold-start - uncap and fill the radiator, elevate the front of the car, start the engine, place the heater on high. Monitor the coolant level.
As the engine warms-up, the fluid level in the radiator should change as the thermostat begins to open. Monitoring coolant level will tell you if the system is "burping" (vacuating air), as well as if the thermostat is bad (rapid changes in coolant level which may result in coolant shooting out the top of the radiator filler neck, worse case). You may see air bubbles as the system "burps" depending on how full the radiator is (hence why you want to keep the radiator filled). As the thermostat opens, radiator fluid changes-over causing coolant level to vary. Allow the coolant fluid to change-over several times (at least three times), continuing to top-off the radiator each time so you can see when the air is passing through to the radiator (ie. burping).
Once you feel the system has finished burping, recap the radiator, shut the engine off, and fill the coolant overflow bottle to the "Warm" level if it is indicated on your overflow bottle. Allow the engine to completely cool-down and recheck the overflow bottle. If the fluid level draws-down it's because the water/coolant contracts slightly as it cools. If there is a "Cold" fill/level mark it may drop below this level which is fine - simply refill to this level and monitor the next few days, and then once a week or each time you get gas if you have no further problems.
If the code you got was a code 52 during the KOER test, it means you probably didn't turn the wheel far or long enough during the power steering pressure switch test.
Assuming that everything else is working correctly, there may be air in the cooling system, and the highest point in the system is around the throttle body/Idle Air Bypass intake plate. Do separate searches using the term "burp" and "burping" and you will find a number of tehcniques on how to do this. Probably the easiest way to burp the coolant system, is by removing a throttle body coolant line. And realize by saying easiest, I mean the easiest way to get the air out of the system, but for some not the easiest technique to do.
The Service Manual procedure does not completely bleed or "burp" the cooling system in the SHO like it does in the non-SHO because of the position of the throttle body, relative to the rest of the cooling system.
From a cold-start - uncap and fill the radiator, elevate the front of the car, start the engine, place the heater on high. Monitor the coolant level.
As the engine warms-up, the fluid level in the radiator should change as the thermostat begins to open. Monitoring coolant level will tell you if the system is "burping" (vacuating air), as well as if the thermostat is bad (rapid changes in coolant level which may result in coolant shooting out the top of the radiator filler neck, worse case). You may see air bubbles as the system "burps" depending on how full the radiator is (hence why you want to keep the radiator filled). As the thermostat opens, radiator fluid changes-over causing coolant level to vary. Allow the coolant fluid to change-over several times (at least three times), continuing to top-off the radiator each time so you can see when the air is passing through to the radiator (ie. burping).
Once you feel the system has finished burping, recap the radiator, shut the engine off, and fill the coolant overflow bottle to the "Warm" level if it is indicated on your overflow bottle. Allow the engine to completely cool-down and recheck the overflow bottle. If the fluid level draws-down it's because the water/coolant contracts slightly as it cools. If there is a "Cold" fill/level mark it may drop below this level which is fine - simply refill to this level and monitor the next few days, and then once a week or each time you get gas if you have no further problems.
Large fluctuations on the temperature gauge are often blamed on thermostat, but that is sometimes not the problem at all. Thermostats are pretty dependable. Go down to Autozone or Advance Auto and get their loaner radiator pressure tester. Last time I did it was a $75 deposit, 100% refundable upon return. Pressure test the system. The SHO cooling system is sensitive to even small pressure leaks. It should hold rated pressure for 2 minutes. If it does not, use your eyes and ears to look for bubbling or telltale drips that are leaks. It may be as simple as a loose hose clamp, or as complex as a bad WP seal. Once the system holds pressure, hook the tester to the radiator cap and see if it holds pressure up to its rating. Unless it does so perfectly, go to the parts store and get a new Motorcraft, and only a Motorcraft, cap. Caps fail far more often than thermostats. Also check the lower radiator hose to make sure it has not become so soft that it is collapsing. New OEM lower hoses are hard to find.
azmattaz06
New Member
Well it's been a feww day's and to be honest my car still overheat's in slow traffic or at stop's and sometime's even when i turn the AC on after a while not even that will cool it down it'll get pretty high up there.. any idea's?
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