The definative '96 - '01 PATS, Fuel Pressure, Injector, and Wiring Harness Thread

[CDW6212R]

I only have the transmission connector chart, saved from one of the times others had posted it.


If the PCM connector(C202) has those trans circuits going in at the same pins, then the change also occurred in the harnesses, the trans harness and/or the engine harness. I suggested starting at the PCM to trace those circuits back to the trans connector. It would be nice to discover that the answer is to just swap the trans harness.

 

[TestPoint]

I hope it is that easy . . . but . . .

Three of the 4 later transmission leads connect to C202 pins listed as 'not used' on the early PCM.

Do we connect the early PCM to the late transmission harness and expect the software to handle it? Probably not without a reflash of the PCM.

Of the 4 transmission circuits in the later system there is only one common to the early version; C202 pin 64, circuit 199, 'Transmission Range Input Sensor'.

I just don't see how swapping a couple pins in a connector is going to fix this.

 

[CDW6212R]

I had not heard of any problem using a later 4R70W in a pre 98 car until this thread. The only problem I knew of was the internal trans harness changes at the case connector, which are the same circuits but moved around inside the connector.

Those circuits I see referred to there in the C202 chart are all related to the range selector, the DTRS. As far as I knew they were compatible for the computer. It's good to check that, and this is a good place to document it.

So two issues, for the DTRS question I'd ask an expert I try to deal with for 4R issues. Let's see if Alan of Dirty Dog performance will tell us how that works, and I noticed that he was a new member here this Spring, very recent.

For the trans case connector, those should be shown in the C202 listings also. If they are the same for the PCM for all years, then the change has to be in the harness(engine or trans) also. I have not dealt with this because my truck and any spare parts I have are all 1998 or 99 parts.

Hmm, I may have a spare 97 engine and trans harness, and I would have thought that they are the same. I need to find out if those harnesses differ, because I will need to use one in my Lincoln.

 

[delexploder]

Man I dont like the sound of that.

 

[delexploder]

I guess im gonna have to get a tuner I cant afford right now and use the 98 pcm. That is if it will work without any of the other pats junk installed. How much dose the tuner cost?

 

[TestPoint]

I have a concern that the fact that someone that has resolved the issues identified has not replied to this thread may be a comment in itself.

I also have a growing fear that the early/late '96-'01 series may well be two distinct non-compatible series. One would think that by now someone would have successfully swapped early/late transmissions at least.

Sure would appreciate it if someone with some actual experience would comment.

 

[TestPoint]

I paid $400 for the SCT device and a custom tune to disable PATS . . . that didn't work. That is why resolving this issue and documenting the solution has become a passion with me.

 

[CDW6212R]

Which parts do you have again, the PCM, engine harness, trans harness, trans? Hopefully something among those is different, to correct.

I have a concern that the fact that someone that has resolved the issues identified has not replied to this thread may be a comment in itself.

I also have a growing fear that the early/late '96-'01 series may well be two distinct non-compatible series. One would think that by now someone would have successfully swapped early/late transmissions at least.

Sure would appreciate it if someone with some actual experience would comment.

There have been at least a few people here who have installed a 98-01 4R into their pre 98 trucks, I'm sure. But recalling which members, the truck, and which trans, I can't name them.

That is why I never mentioned the DTRS signals, I didn't know that they aren't identical listed for each PCM. I think those other members simply rewired the one trans case connector, and it worked properly.


For delexploder, I suggest concentrating on that trans case wiring immediately, that is definitely mixed up in your application. Find the wiring schematics chart etc, for the connectors of the engine harness, both ends. Those trans circuits run through the trans harness into the engine harness, then to the PCM. I think the solution for yours will be to swap a few of those wires around at one of those connectors.

 

[delexploder]

I agree theres gotta be a way to make this work and im sure someone on here has done it. Im thinking its gonna involve making the harness from the pcm all the way to the tranny and even the tranny side match the earlyer setup.

 

[delexploder]

Snoranger I see you've been following this any thoughts? Lol

 

[CDW6212R]

I agree theres gotta be a way to make this work and im sure someone on here has done it. Im thinking its gonna involve making the harness from the pcm all the way to the tranny and even the tranny side match the earlyer setup.

Find the two wiring lists for the two connectors, and we can figure it out.

 

[delexploder]

I'll try im using a Droid tablet so it may take a while

 

[delexploder]

Ok here's my thoughts the harness matches the trans so the problem is at the other end...Im using the 98 gcm ( trans controller) and im thinking its maybe a pin issue there and or at the 42 pin connection plug... and how many pins were off at the pcm? Remember my truck side wiring is 97 sohc and 5r55e

 

[delexploder]

Dose this make sense or do you think im way off?

 

[TestPoint]

I think you are using the late 4R70W harness which connects to your late 302 harness which connects to the early PCM. Post #27 identifies the PCM interface differences and post #31 has the transmission end.

 

[CDW6212R]

... 98 gcm ( trans controller)...

What is that? You said the PCM is a 1997 302 Explorer, that controls the trans.

There is a connector for the engine to transmission harnesses. The wiring could be crossed back in those harnesses, ending with the PCM connector circuits lined up correctly(for a 96/97 all stock parts).

If the internal trans functions are the same at the computer, then the wiring is all that needs to be corrected, to use the late wiring with the early PCM.

 

[delexploder]

Yes I have 99 motor and trans 98 wiring harness 98 gem 96 fuelrails and injectors and a 97 pcm so basically im setup as a 98 trying to run a 97 pcm. I'll look at the pcm connection but what I was also wondering was if the gem being plugged into the trucks wiring or the few diferant pins at the 42 pin connector might come into play?

 

[CDW6212R]

GEM module, that is in the dash and isn't part of controlling the engine or transmission.

It does matter for the transfer case if you have 4WD. There are two GEMS for the Explorer models, one for 4WD, and the other for everything else.

For your 97 truck, you must have a 97 GEM. Did you change from 4WD to AWD, or has it stayed the same as a 2WD?

 

[delexploder]

Sorry just getting back I put the 2wd gem from the 98 stuff I got from turdle

 

[CDW6212R]

Look at the computer chart on the first page, see pin #s 1, 27, 37, 54, 81, 91, and 97.

Those are the circuits which lead to the transmission case connector. Those need to be compared between both PCM model ranges, 96/97, and 98-01. The circuits are identical, and should be in the same place for each PCM, confirm that.

Then make sure that each of those wires leads from the PCM pin to the trans connector pin, in the charts. I'm betting that they don't, that the wires probably start in the same place(PCM), and end at different locations(trans).