I recently had an accident in a parking lot and damaged the fender on my 2005 STR. The fender was pulled away from the car and tore the wire harness with it. I repaired all the visible mangled/broken wires. This was the front passenger side.

The car starts and runs but is in restricted performance mode. With the car off but the key on I can clear the codes and they all immediately come back without starting the car. So they appear to be hard faults. Car was running perfect before the accident and had no codes of any kind.

Now I have P0102 MAF Circuit Low, P0405 EGR Purge Valve Shorted, P0445 EVAP circuit shorted, P0447 EVAP circuit open.

Seems reasonable as the shorts and opens point to wire problems which were caused by the wreck. But the problem is none of those items are near the front passenger side and I have now traced the wires are none of those items have wires in the harness on the passenger fender side.

Using the Jaguar electrical guide I pull the ECM plug (That's a lot of fun!) to do pin checks and wire checks as per the electrical guide suggestions. There were 7 wires listed. All the wires check fine with no shorts or opens.

I know the car died and the check engine light/restricted performance came on the second the car was hit so it all happened at once. Since I can't find any wire problems I wonder if the shorting out of the wire harness during the wreck might have blown something in the ECM?

Looking at my DTC codes further there are statements like MAF sensor to ECM sensing circuit, ECM drive circuit short to ground, EVAP purge valve to ECM drive circuit open circuit, EGR to ECM drive circuit Open or high resistance. EVAP canister close valve to ECM driver circuit open or short circuit.

Since I think all the driver circuits are inside the ECM and I have no way of checking them could these codes be from a damaged ECM? I found about 5 or 6 wires mashed and cut so things were shorted together.

Should I chance another ECM or get mine repaired?
Or is it something different?
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Ouch! Not good news - but stuff happens.

I'm not sure who would/might know. The techs? (Bob, Steve, Bill, ...)

Many times the PCM can detect shorts etc and it survives. I don't know whether that's just "usually" or "nearly always" or what, sorry.

I'd be tempted to call one or more of the techs, offer to pay to consult and get their view. I really don't know any better - they know a LOT.

You could send the PCM to one of the repair places (ASI etc) as an alternative.

As you know, you could buy another (used) STR PCM but that leads into anti-theft if not programmed with care. Still, doable. Again, a tech seems a good choice.

 

Thinking about what you said I have found a used ECM for around $150-$200. This might be a cheaper way to trouble shoot. I can get mine repaired for about $250-$300 so they are around and you can get them if needed.Just not sure it's my ECM yet? It sure points to it.

As you said I think it needs to be programmed but the car should start and run and at least show me if the hard error codes are still there or not?

Don't mind chasing wiring problems but at this point I don't think there are any. I have the main ECM plug off and can check the wires directly to the sensors from the main plug. They all check good and I have checked and rechecked the passenger fender area where the wires were damaged for additional problems and it all looks good too.
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Where are you located?

 

If reprogrammed it should then run the car. (If not reflashed it'll anti-theft.)

I really doubt it's the PCM that's at fault so would be trying to find another cause - but as you've done that... I'm stuck!

 

We don't hear from Brutal much anymore. Since you are in his area can you possibly get in touch with him? Maybe you have already.

 

I am in the Houston area which is where Brutal is. I have not contacted him yet. I actually used Bill while the car was still under warranty and have used him several times afterwards. Massive Jaguar Knowledge!!

But if I need to get another PCM I think I will to check to see if he will program it. I really don't see anything else to check at this point?
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I would not be surprised if he has a PCM or where to get one

 

Sorry to read about your parking lot troubles. That's a real shame, but glad to hear you are attempting to repair your vehicle. We all know that we can only get pennies for these S-Types nowadays although the STRs should command a bit more money....

If I were you I would contact Brutal right away. Why keep chasing guesses when he can most likely pinpoint your issue(s) within a minimum timeframe?

 

Yes that's a good point but Bill is very busy and any troubleshooting that can save him time is worthwhile.

I have removed the ECM and it's part number 4R83-10K975-DA. Sprayed the pins with contact cleaner and made and broke the connection several times to break up corrosion. But no change when it's all hooked back up.

Seems rare as I can find the 2003 STR computers in several places but they changed the ECM I guess for the 2005 and up STR's.

Brutal has recomended GOECM.com and I have called them. A repair/rebuild with lifetime warranty is $395 for my computer.
So that's a possibility too.
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Well the ECM was sent off to SIA electronics for repair. Turns out I was correct that the ECU was damaged from the shorted wires.

NOW the problem is the ECM is irreparable and they are sending it back without even charging the diagnostic fee! That is very fair but I could not find a used ECU that matched my part number before and Brutal told me that you can't change the ECM regardless of programing??

Anyone change an ECM out on an S Type before? Can you post what steps were taken to make it work?

I have delt with a number of module problems over the years but never the ECM as that is very rare. This is my first one in fact. ALL the other modules were reprogrammed by the dealer without problems.
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Sorry to hear that you're in such a tough spot. Hope you manage to come up with a workable (and relatively affordable) solution. Keep us posted....

 

Wow, that's bad news.

The STR's PCM had a big change at least once (went from a twin, lower performance, CPU to a single much faster one that's aka PanPAG; all are Denso make). So you'd need the right kind. They can be reflashed (technically speaking) but I don't know what IDS/WDS/etc is able/willing to do.

I'd PM/call motorcarman and xjrguy (as well as Brutal) as they might know.

I think if you could get the matching kind of PCM (twin or single CPU, whichever yours now is) then they might be able to reflash it but ask them.

Failing that I suppose if you got the matching set (again the right PCM) needed for the immo then that ought to work. They can probably tell you which modules you'd need.

I _think_ your PCM will be the kind I also have i.e. pre-PanPAG (I think PanPAG is 2006MY-on), so the twin-cpu kind. hmm... try a PM to Cambo as he knows plenty about this stuff, too.

The VID block is likely involved and Bob has posted at least one PDF about that plus he knows more I am pretty sure.

In case you want to look at yours, I think you'll find two large chips (256-pin) marked SH7055. I think the PanPAG is SH7058.

 

Just a quick update. I found a ECU in the UK!!!

Will be here this week and the price looks to be pretty good at around $220 with shipping.

Got the fender and passenger headlight already. Those special STR HID's are HARD to find!!
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Here is some info about the VID block.

bob

 

Thank you Bob for that very detailed document!

I understand the module reprogramming much better now. But that 15 page document just further reinforces the idea that the ECU can and does get reprogrammed without anything special??

It has specific instructions for installing a new ECU and I found out even if the VID block is bad,missing or wrong. The factory has a copy of every VID for every car they have built. So you can't loose the VID because you can retrieve it from Jaguar's database.

Next step is to call Jaguar service directly and see what they say. Conflicting information from different people I guess I need to go back to the Mother ship on this one.
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Commonly called As Built data.

It might be a little different due to options etc but should always work. In your case the VID (they change the name periodically but it means the same) should be OK.

You could do with a tech nearby to save you time & money.

 

Good luck getting a VID upload from Jaguar. I used to be a dealer tech. I read some of that tsb. If we were having problems with a certain car we would send the vid block off to jag and they would change it and send it back.

I don't see why you can't change ECM, but you will need jaguar software to program it. Basically security side of things. Pretty sure the instrument pack deals with security side so you have to match ECM to IP.

Hope I'm not telling you something you didn't already know.

 

Worth saying. I don't think he'll need to send the VID block away, just can copy it to the new (but used) PCM.

+1 on security (immo)

Brutal?

 

+2