I'd like to give more info, but all I know is what I read. Armchair Q-back instead of in the trenches. He does say that a dealer should be able to use their software to isolate the problem. The switch is a rotary switch on the trans which tells the ECU which gear was selected. Evidently a failure can send erroneous signals to the ECU triggering many seemingly unrelated faults.
Mike

 

Up until now the only the only problem I have seen is that the shifter selector switch would have an intermittent starting problem “N” & “P” I have not heard of erroneous signals to the ECU. At this point I would not rule it out. The only problem I see is that the selector switch is not a cheap item$300.00 less for a used one if you can find one if you elect to change it. How do you test it to know?

 

I just happened to read this thread and everything I see points to a connector problem. The main clue is the fact that it is intermittent which is a classic symptom of an intermittent connection. We have all seen (in other threads) that some of the connectors in the car used non-gold terminals and in some cases mixed metal. This will typically generate failures that appear to be random and replacing parts down stream will not fix anything. This is also supported by codes that implicate other modules, so there is apparently something common between them.

I haven't traced the wiring diagrams but I suspect there is some common wiring point where the units that are showing in the codes converge. This is probably where the problem is. If you can track that point down then I suggest using some contact cleaner before replacing the harness. CRC makes some good products for this purpose. Remaking the connection can provide a temporary fix but since the root cause still exists, the problem will return.

You can also start with the throttle body, and work your way back through the harness, cleaning the connectors in that path.

I also noted the comments regarding the throttle body pot. There are products that are designed for cleaning and lubricating potentiometers and I have put it on my list to do this given the exorbitant cost of throttle bodies. A similar problem affects the pots in the steering column. These pots are made using a thin deposited resistive material that the wiper runs over. Dirt between the wiper and the resistive surface acts like sandpaper to wear a hole.

Being in the OEM electronics business for the past 40+ years I can say that the cost of parts is all about volume. Look at how many Corvettes there are versus Jaguars. The Corvette parts are also shared with other GM cars so the volume is even greater. This gives the suppliers a lot of incentive to keep things alive. Our cars share parts with some Lincoln's and Range Rover but only a few. We should be happy that any parts are available.

 

ECM is rebuilt and on the way back home from the joint in Rogersville, TN.
He says I need to have the codes that may still be on it removed by a shop or hard reset which he said woud clear it. He said take batt cables off batt and hold them together for a few min. Will this work since the ECM has been OUT OF THE CAR and no batt current to it???? Or do I just go ahead and plug the unit back in and then pull cables and hold together for 3 min or so as they said???
They do say to make sure I have a FULL charge on the battery before setting it back in.

 

I would do as he says. As for the hard reset I did not think it would clear the codes that are set in the system. Did they say they found a problem?

 

They said it failed the bench test so they went through it and fixed all know issues with 97 units and upgraded were they could.

 

He said that I would need to take it to a shop that could clear the codes prev set. I thought with ANY computer in a modern car jsut taking off the battery cable for a bit cleared them. Anyways, then he said that I could do a hard reset by just holding the two batt cables on each other for a few min and that would clear the codes.

 

Cutting power to the car does not reset the OBD codes. Neither does shorting the battery cables. Codes will reset through 'drive cycles' after repair or the use of a code reader.

 

so just driving it and assuming the car is fixed the codes will be wiped out? I thought on any modern car if the code is tripped and you get the CEL even if issue goes away, the cel goes out, the code stays recorded till power is taken off car which cleared the codes. I have been told this on other car mokes, just not JAG?

 

We will find out if it was the problem when you get it back and install it.

 

with my luck......

 

ABS mod replaced in 2001, so jsut maybe that is not a problem part since it is newer, with only 50k on it. WHO KNOWS. ha ha ha

 

when do you get your ECU back from the rebuild?

 

Still in a holding pattern for that. Hopefully today. Have to put battery on charger to get it up to full charge. Been cold as hell here, so I am sure it needs a little charg'in.
My plan is to put the computer back in while batt is connected, the pull batt lines and to the hard reset I was told would clear the codes, then hook her back up and see what happens. Ganna check some connections I did not the last time I was in the car also.

 

Still no computer yet. I did put trickle charger on batt. I checked the two posts at the fuse boxes in engine area, connections clean but I still took them apart and reseated.

 

On the 97 is the Tract Control part of the ABS module????

Repair Operations - (AWA)
SRO Number SRO Description
706020 ABS CONTROL MODULE - WITH TRACTION CONTROL - RENEW


based on that it is all on pc?

 

What are the CHANCES thhat the battery in the car is ORIG to the car, 1997??? The battery has no markings to show me a date. Any code on it to tell me???
I ask this becuase the prev one owner took this car in for EVERYTHING that needed fixed. Batt went dead in 98 cause it sat for 3 weeks. They just checked fluid levels in it and it was ok. No other mention of battery issues or anything. It has a JAG issued matt in it. I just wonder it if is still orig which now some 15 years later is working? Naaaaaah can't be.

 

If you are concerned about the battery take it out and have it checked at AutoZone, PepBoys or Sears and see what they say. Battery testing has come a long way from years past and the test will give you peace of mind.

 

As for your question on the ABS & Traction Control look at Fig 6.1 of this oneline for your car. They are one in the same. http://www.gusglikas.com/images/Auto.../jagxk1997.pdf

 

Man I sware the shop that did the TB swapping on my car said the TC was part of the TB. Seems it is part of the ABS unit.