Digital Instrument Cluster - testing procedures

[Storm-Chaser]

I found a digital cluster in a '95 Sable LS (along with EATC and JBL sound). The problem is that the windshield was busted through in two locations above the dash, as they had previously moved the car using a fork-lift.

Anyhow, there's no indication that any significant amount of water got into the cluster, but before i expend the energy and time, I'd like to pre-test as much of the cluster as possible.

Some of the images of jelloslug's conversion are missing, and his site mainly covers simply the installation. The EVTM gives circuit and pin-out information needed, but nothing in the component testing section. Hoping someone will have or know of a manual for testing/troubleshooting/repairing the digital clusters.

 

[only1me]

Here you go.

http://www.shoforum.com/showthread.php?t=69504&highlight=digital+cluster

 

[jelloslug]

Take a look at the pinouts on my install site. On the small black connector you will need to hook up all the grounds and anything labeled "B+", "power", "acc", "hot in run", etc. This should power it up.

 

[jelloslug]

As for repairing them, I have never found anything specific on troubleshooting the cluster other than just checking the connections. Anything more complex and Ford just said to change the cluster and send it in the their repair facility.

 

[Storm-Chaser]

I already have the power and ground connections identified from the EVTM - thanks.

Here you go.

http://www.shoforum.com/showthread.php?t=69504&highlight=digital+cluster

Take a look at the pinouts on my install site. On the small black connector you will need to hook up all the grounds and anything labeled "B+", "power", "acc", "hot in run", etc. This should power it up.

Generally when trouble-shooting a malfunction, there can be up to three areas to reference - the Service Manual often contains pinpoint tests; the EVTM may contain troubleshooting hints within the component schematic section; and/or the EVTM may contain component testing procedures following the schematic sections. Often, when there are unique components limited to a few vehicles (eg. the DIS) or several vehicle product lines (eg. the EATC), a component-specific manual was published.

The Service Manual does include 20 pages of "diagnosis and testing" in the pinpoint testing section. The EVTM only contains a single troubleshooting hint for the speedometer in the schematic section (last step ends with "Check Instrument Cluster"), and nothing in the Component Testing section. I was hoping that someone here may have come across a Digital Instrument Cluster manual, or additional testing/troubleshooting procedures.

I have 30-days to return the cluster if it's bad, but it's simply not worth spending additional money to send-in a salvage yard part for repair - I'll simply wait for another one to pop-up.


Two additional questions in reference to the Digital instrument cluster. First, the parts manual lists three different fuel pumps for the '93-'95 Taurus (six total for 92-95):

• 93-95 SHO
  
  
• To 1-94 w/Electronic Cluster
  
  
• After 1-94 w/Electronic Cluster

Did you change your fuel pump? If not, have you had any issues with the accuracy of the fuel quantity readout?


Second, have you found a way around the 6,600 RPM limitation for the tach?

As for repairing them, I have never found anything specific on troubleshooting the cluster other than just checking the connections. Anything more complex and Ford just said to change the cluster and send it in the their repair facility.

 

[jelloslug]

Some of the clusters I have gotten have an 800 number to call for tech help. I have never called it though. AFAIK there is no such thing as a digital cluster troubleshooting guide. I also have never found any kind of self test routine for this cluster. I have not ever had to change anything on the fuel pump or float when doing a conversion. In fact a number of SHOs that have had poorly functioning fuel gages worked better after the swap. The Fuel Computer functions, on the other hand, use the Fuel Flow pin on the ECU for there signal. It is documented on the MTX pin out but I have never located it on the ATX SHO ECU. The 6600 RPM limit is hard coded into the cluster AFAIK. When you hit 6600 the Tach just jumps to full readout. I'm sure someone with the proper electronics knowledge (not me ) could possible get into the RAM of the cluster and might be able to reprogram something. Also for your information; there are at least 4 different Taurus digital clusters of this style: Green with 85 MPH top speed, Blue with 85 MPH top speed, Blue with 125~ top speed, and Blue with Flex Fuel computer. There is a compatible cluster from the Windstars also but it's tach only goes to 6000 RPM.

 

[jelloslug]

Another thing: If you wanted to you could send me your cluster and I could put it in my car. We would know quickly if it works or not.

 

[Devin]

Is the MPH info sent from the PCM more accurate at higher speeds than the cable driven kind?

 

[jelloslug]

Is the MPH info sent from the PCM more accurate at higher speeds than the cable driven kind?

I would say it is more accurate. I have tested with mile markers and a stopwatch and many different speed from 35 to 85 MPH and it was dead on perfect every time. For those that don't like the digital tach you can turn it off and use an aftermarket tach mounted somewhere else.

 

[93rev2sev]

12V motorcycle battery + small hammer = test it in the junk yard.

 

[WI93SHO]

Also for your information; there are at least 4 different Taurus digital clusters of this style: Green with 85 MPH top speed, Blue with 85 MPH top speed, Blue with 125~ top speed, and Blue with Flex Fuel computer. There is a compatible cluster from the Windstars also but it's tach only goes to 6000 RPM.

How can I tell these apart at the jy? And is the blue a blue blue or a green blue like the gen IIs?

I sounds like you are quite an expert on this, I would ask that you could do an FAQ or build on your existing writeup in case you were hit by a bus tomorrow.

 

[Devin]

There are a few threads, including one of mine that has a decent bit of info in them too.

 

[jelloslug]

How can I tell these apart at the jy? And is the blue a blue blue or a green blue like the gen IIs?

I sounds like you are quite an expert on this, I would ask that you could do an FAQ or build on your existing writeup in case you were hit by a bus tomorrow.

The green ones are in 90-91 Taurus and Sables, the Blue ones are in 92-95 Sables ( it seems that the later Sables has the 125 MPH clusters) and the Flex Fuel ones were in 92-95 Tauruses.

 

[Storm-Chaser]

I did see the (800) number on the orange-tag on the back of the cluster. I wonder if this is "ford" number or third party manufacturer/remanufacturer.

The 20 pages of pinpoint tests is in Section 13-01 of the 1994 Service Manual I checked.

The poor performance of fuel gauges you mention may be due to the instrument cluster gauge and not the fuel pump sender. The only problem I've ever had was with the sender, but I do know others that have had gauge problems or failures.

My understanding was that the fuel quantity displayed is based on the fuel sender, and fuel economy/miles-to-go is calculated based on the fuel metered to the injectors compared to fuel remaining averaged with fuel economy since the last fuel computer reset.

I am curious as to where pin #34 is documented for the 3.0L MTX PCM (ECU) out.

Some of the clusters I have gotten have an 800 number to call for tech help. I have never called it though. AFAIK there is no such thing as a digital cluster troubleshooting guide. I also have never found any kind of self test routine for this cluster. I have not ever had to change anything on the fuel pump or float when doing a conversion. In fact a number of SHOs that have had poorly functioning fuel gages worked better after the swap. The Fuel Computer functions, on the other hand, use the Fuel Flow pin on the ECU for there signal. It is documented on the MTX pin out but I have never located it on the ATX SHO ECU. The 6600 RPM limit is hard coded into the cluster AFAIK. When you hit 6600 the Tach just jumps to full readout. I'm sure someone with the proper electronics knowledge (not me ) could possible get into the RAM of the cluster and might be able to reprogram something. Also for your information; there are at least 4 different Taurus digital clusters of this style: Green with 85 MPH top speed, Blue with 85 MPH top speed, Blue with 125~ top speed, and Blue with Flex Fuel computer. There is a compatible cluster from the Windstars also but it's tach only goes to 6000 RPM.

 

[Storm-Chaser]

And the reason for the small hammer (versus jumper-wire) is . . . .

12V motorcycle battery + small hammer = test it in the junk yard.

 

[Storm-Chaser]

There should be several OEM Engineering numbers on the instrument cluster. The two on the unit I am looking at, both start with F5DF- (which decodes to 199x model-years [F]; 5 for the 5th manufacturing year; D for Taurus/Sable model-line)

How can I tell these apart at the jy? And is the blue a blue blue or a green blue like the gen IIs?

I sounds like you are quite an expert on this, I would ask that you could do an FAQ or build on your existing writeup in case you were hit by a bus tomorrow.

 

[Storm-Chaser]

I did review the other threads, and plan on reviewing them again before moving forward with this.


Another question - the non-standard connector (black, 20-pin, C256) is not an OEM product but made by AMP, as is the male connector that is hard-wired to the PCB. AMP is a very large multi-national electronics OE supplier. Did anyone look into a source for these two connectors or their pins?

There are a few threads, including one of mine that has a decent bit of info in them too.

 

[jelloslug]

I have a large, fold outs set of wiring diagrams from Ford for the 1990 Taurus/Sable. The pin for the Fuel Flow is documented on that set. I have never seen it listed on other years of the Ford wiring diagram but that pin functions correctly on all MTX SHO ECUs AFAIK. AMP makes most of the connectors that Ford uses. The black connector on the cluster is in fact a part of a series of OEM connectors that Ford uses. They are the same series that are on the JBL radio for the 6 and 8 pin rectangular connectors, the 2nd gen VF display clock and the redundant radio controls. These style connectors are also used in many other '90s and later era Ford vehicles. I have a Crown Vic digital cluster that has 2 similar connectors, just with fewer pins and I have a Mark VIII message center that uses a similar setup.

 

[ohioshodude]

i never could get one of these to power up outside if the vehicle. you can always make a custom one as i did. its a 125mph speedo and i swapped over the green display (to match the gen I) only way to test this easily is to power the car in the junkyard but its really not that hard to pull one.. just make sure you get as much wire are you can if you are cutting it out.

 

[Storm-Chaser]

Please elaborate!

Did you swap gauges between different year clusters? Between different application clusters? Or was it a Gen II cluster that you converted from blue-green, to green? Any other documentation?

i never could get one of these to power up outside if the vehicle. you can always make a custom one as i did. its a 125mph speedo and i swapped over the green display (to match the gen I) only way to test this easily is to power the car in the junkyard but its really not that hard to pull one.. just make sure you get as much wire are you can if you are cutting it out.