climate control blowing fuse

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mclark

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Try this for the no overdrive situation.

http://www.wikisho.com/wiki/I_have_an_ATX,_and_my_4th_gear_stopped_working!

I see that link does not work as well as it should, try this:
Kevin Airth had a problem with his 4th gear not working in his automatic transmission SHO, and found the following solution :

A big thanks to Doug Lewis and Micheal Anderson! My 93 ATX had lost 4th. gear but otherwise worked OK. Micheal posted the same problem and Doug was able to figure it out. The C-clip on the O/D servo had broken, preventing the transmission from shifting into 4th. gear. The O/D servo cover is on the drivers side of the transmission on the firewall side,down low by the steering rack. Remove the drivers side front tire and you can get to the 3-8 mm bolts on the cover. I removed the cover and the servo,found the broken clip laying inside the transmission. Replaced it for less than $1 and now have 4th gear back!
Removed the servo and both clips was intact .
 

mclark

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friendly F Y I,, while at steady speed and applying accelerator to pass, the first thing the transmission does is release the torque converter lock up clutch. even though the engine RPMs jump up the transmission remains in the same gear. that is not a shift to "passing gear", but the de-coupling allows the engine to rev higher where it has more power. the RPM difference is inside the now slipping torque converter. if the computer senses a need for even more power a down shift to the most appropriate gear occurs.

during normal acceleration there will be 3 gear shifts, 1-2 2-3 3-4. then the computer engages the torque converter lockup clutch and the engine RPMs drop. that is not a 4th shifting of gears but is mistakenly perceived as one.

the 3000 RPMS at 70 mph indicate the transmission is in top gear, 4th, and the torque converter lock up clutch is not engaged which allows the engine to rev higher from 2500 locked to 3000 unlocked.

at this point you cannot "downshift to passing gear" because you're already in "passing gear" by virtue of the torque converter being unlocked.


make sense? or do I need to add some even deeper B.S.


Perry
Make sense what you r saying, but i am stating that at 70mph my tach is 3000rpm when it should be 2500rpm at 70mph, and when i go to pass there is no down or upshifts , even at WOT.
 

sperold

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I just switched over to my winter car (90) and the obvious difference is it is a standard and yours is an automatic; but my car at 2500 rpm, the speedo says 64 mph. when in 5th gear.
So the automatic cars rev quite a bit lower than the standards, if 2500 rpms give you 70 mph.

It is good that you looked at the overdrive clip, so now it seems it is narrowed down to the lock-up torque converter, which I have always heard eliminates the 10 % "slip" that older automatics had to endure.

I would get an EVTM (Electrical and Vacuum Troubleshooting Manual) for a 95 Taurus (often less than $20.00 on ebay and find the signal that initiates the lock-up and see if it is happening.
 

mclark

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How long have you owned this car and how long ago was the tranny rebuild?
I have owned the SHO for 23 years and the trany was rebuilt five years ago at Coleman Taylor , the SHO had 239000 miles on the rebuild and now it has 264000 miles, only 25000 miles on the rebuilt trans .
 

rubydist

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mclark, the way this works is you ask a question on the forum, and people who know more about it give you answers. If you ignore the answers or argue with the answers, then you stop getting input from people who actually know what they are talking about.

There was no point in taking the o/d servo out, because you already know you have 4th gear. You know you have 4th gear for several reasons, including that you have 3 upshifts and that the cruising rpm are 3000 not 3500. The problem you have is that the torque converter does not lock up. The torque converter not locking up has nothing whatsoever to do with the o/d servo.

Now you can keep asking about why you don't have a 4th gear, but that just tells us you don't listen to the direction you are given by people who know what they are talking about, so those same people will stop answering you. Then you will only get speculation by people who aren't helping you at all, because you are looking in the wrong place. That may be entertaining in a demented sort of way, but its not helping you get your car fixed.

So, if you want any more help on this topic, read the transmission codes and tell us what they are.
 

mclark

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and the hard shifting was recently or since rebuild?
Hard shifting started after the SHO had set up for about year and half due to engine failure , had the engine replaced about eight months ago and its been doing it every since .
 

mclark

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mclark, the way this works is you ask a question on the forum, and people who know more about it give you answers. If you ignore the answers or argue with the answers, then you stop getting input from people who actually know what they are talking about.

There was no point in taking the o/d servo out, because you already know you have 4th gear. You know you have 4th gear for several reasons, including that you have 3 upshifts and that the cruising rpm are 3000 not 3500. The problem you have is that the torque converter does not lock up. The torque converter not locking up has nothing whatsoever to do with the o/d servo.

Now you can keep asking about why you don't have a 4th gear, but that just tells us you don't listen to the direction you are given by people who know what they are talking about, so those same people will stop answering you. Then you will only get speculation by people who aren't helping you at all, because you are looking in the wrong place. That may be entertaining in a demented sort of way, but its not helping you get your car fixed.

So, if you want any more help on this topic, read the transmission codes and tell us what they are.
10-4 copy that , was only following up on a reply that he posted his Sho had the same symptoms.
 

sperold

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The "sitting around" part does not sound like an issue, but the engine swap part may be a clue. Every engine swap involves handling both the wiring harnesses and the torque converter. Most swaps involve not connecting all the harness plugs at first start-up and require a go-over to catch the offender. Less often, a plug is broke or a wire is compromised, and very seldom, the connection is fouled enough to be faulty.

Go to your Ford store, or a place that subscribes to the vast repair data on-line and get some pictures on where your connection points are on the automatic and where the wiring originates, and the colour of the wires and the connectors. Get them to divulge more about the lock-up wiring, as that seems to be the key.

Since your are handy enough to get that cover off to look at the clips, this exercise will be much easier and much more rewarding.
Get that EVTM document in the mean time, as it can tell you a lot of this information. You may find that the lock out wiring and the 1st to 2nd shift solenoid or clutch share the same connector.

I doubt if the engine swap affected your torque converter, unless there was some incompetence; like letting it fall off the input shaft and bouncing it off the floor. But that possibility is way out there and can be virtually eliminated.
 
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luigisho

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Hard shifting started after the SHO had set up for about year and half due to engine failure , had the engine replaced about eight months ago and its been doing it every since .
That's info that helps. I ask weird questions to see if there is stuff like this missing from the equation. Which happens alot around here. If someone messed with something and now it doesn't work right that's good intel. Ruby's advice is always good, and codes help point the way. Sperold's advice too. You know the places to start looking so check those and check back.
 

mclark

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That's info that helps. I ask weird questions to see if there is stuff like this missing from the equation. Which happens alot around here. If someone messed with something and now it doesn't work right that's good intel. Ruby's advice is always good, and codes help point the way. Sperold's advice too. You know the places to start looking so check those and check back.
10-4 I appreciate that and will check back .
 

pjtoledo

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using a 1995 EVTM.
the converter lockup signal enters the transaxle on pin 3 of connector C168. its a triangular connector, 2 rows of 4 and 1 row of 2 pins. wire is P/Y.
the signal originates in the computer and exits on pin 53.
the computer monitors several sensors to decide when to lock up the torque converter clutch SOLENOID.
transmission fluid temperature sensor, throttle position sensor, turbine shaft speed sensor. maybe more, that's all I found quickly going thru the 1995 EVTM.

please note the signal only activates the lockup solenoid. the solenoid then routes fluid to do the actual locking.
 
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sperold

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The connector C168 that Pjtoledo mentioned above is on top of the transaxle in the engine compartment.

The transaxle gets the shifter location (P R N D) from the transmission Range Sensor, connector pin 5, wire 359 GY / Y.

It gets its power from the CCRM on pins 2 and 7. It is the raw power it uses to power the torque converter clutch solenoid, the shift solenoids and the pressure control solenoid. Wire 361 R (2 wires).

The brains behind the manipulation of these solenoids comes from the Powertrain Control Module (PCM). The information comes from the Intake Air Temp Sensor (IAT), Throttle Position Sensor (TR), Barometric Pressure Sensor (BARO), Engine Coolant Temperature (ECT), Vehicle Speed Sensor (VSS), and the Turbine Shaft Speed Sensor), and the Transmission Temperature Sensor which is this case, comes from the transaxle itself.
The connector pin outs that enable this manipulation are as follows:
Torque Converter Clutch Solenoid Pin 3, wire 480 P / Y,
Shift Solenoid 1, pin 1, wire 237 O / Y,
Shift Solenoid 2, pin 5 wire 315 P/ O,
Shift Solenoid 3, pin 8, wire 971 PK /BK,
Pressure Control Solenoid, pin 10, wire 925 W / Y.
Transmission Fluid Temp Sensor, pin 5, wire 923 O /BK.
 

pjtoledo

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after reading sperold's post and further reading:

keep in mind the circuits are "ready hi", which means power is always applied to a device but no current will flow until the PCM connects the ground/return to enable a device.

first off, the service manual specifically states to run the codes and fix any issues before screwing with the transmission.

on the connector C168 pin 2 is power for the three shift solenoids, pin 7 is for clutch and EPC (pressure). 2 & 7 are spliced/common back in the harness.
the PCM grounds pin 53 which is 3 on the transmission connector to enable current flow and activate the solenoid. so you should see 12v on pins 2 & 7. if the torque converter solenoid IS NOT being told to engage there should be 12v at pin 3. if it is being told to engage (you are driving) it will read zero, or damn close to 0. those are at the tranny connector.

for electrical gremlins:
in the diagnostics & troubleshooting section it calls out the sensors and says to run torque converter clutch test, and run on board diagnostics. get the codes.

for mechanical/hydraulic gremlins it could be almost anything,,,low EPC pressure, bolts not tight on valve body, gaskets, seals, any of the plungers in the valve body, and of course the solenoid itself.

I have found a wire discrepancy.
1995 EVTM calls the wire between PCM pin 53 and transmission pin 3 circuit 480 P/Y ,
the 1995 service manual calls the same wire circuit 224 T/W
hey, at least the pins are the same.
 
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mclark

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after reading sperold's post and further reading:

keep in mind the circuits are "ready hi", which means power is always applied to a device but no current will flow until the PCM connects the ground/return to enable a device.

first off, the service manual specifically states to run the codes and fix any issues before screwing with the transmission.

on the connector C168 pin 2 is power for the three shift solenoids, pin 7 is for clutch and EPC (pressure). 2 & 7 are spliced/common back in the harness.
the PCM grounds pin 53 which is 3 on the transmission connector to enable current flow and activate the solenoid. so you should see 12v on pins 2 & 7. if the torque converter solenoid IS NOT being told to engage there should be 12v at pin 3. if it is being told to engage (you are driving) it will read zero, or damn close to 0. those are at the tranny connector.

for electrical gremlins:
in the diagnostics & troubleshooting section it calls out the sensors and says to run torque converter clutch test, and run on board diagnostics. get the codes.

for mechanical/hydraulic gremlins it could be almost anything,,,low EPC pressure, bolts not tight on valve body, gaskets, seals, any of the plungers in the valve body, and of course the solenoid itself.

I have found a wire discrepancy.
1995 EVTM calls the wire between PCM pin 53 and transmission pin 3 circuit 480 P/Y ,
the 1995 service manual calls the same wire circuit 224 T/W
hey, at least the pins are the same.
Hey guys just want to say thanks for all the input and info that was given, most of all thanks for the patients that you guys had with me and the continued responses, i really appreciate the patients . Follow up on the SHO , with all the info given i didn't have the tools nor the skills to perform them , so i decided to take it to a guy who had just rebuilt my daughters 1.8 turbo VW beetle trans, after having the SHO for a day he called me and stated that the wire on the VSS connector pigtail was lose , he ordered the pigtail installed it and now the SHO has no more hard shifts , and at 70 mph the tach is at 2500 rpm instead of 3000 rpm . Hey guys once again i really appreciate your RESPONSES & PATIENTS . Thanks .
 
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