'98 Stratus issues

[ramenth]

I'm trying to help out a young lady here with a 2.5L Stratus. No spark. After running the initial poinpoint tests I found the coil driver wire had a break in it after some nitwit decided the lower rad hose clamp needed to be facing up instead of facing off to the side. Anyway, repaired the break in the wire and now showing 1.9ohms. Flow chart is showing that anything below 5ohms is PCM (Above 5ohms is what lead me to the ground out issue.)

Now to the question. After speaking to a parts counter guy at Chrysler I was told the PCM could only be sourced by Mopar ($500+) and needs to be flashed for the car. After speaking to a tech at Chrysler he said it could be sourced from a parts car as long as the parts car had the same powertrain, non security system.

I know the parts guy's job is to sell parts, but I need to know who's right in this case.

I've done a few PCM's when I was at Ford and they were plug and play. Can I source one from a donor car for Chrysler?

 

[gunbunny]

look at next. Computer had a brain fart.

 

[gunbunny]

You're not going to like this answer.
Maybe yes, maybe no. You may be able to use a donor PCM, but it will have to be flashed on the car. That's when your going to get your answer.
When the car powers up, there is a handshake protocol.
The PCM wakes up and searches for the body controller and/or the trans controller. The VIN's must match for the system to work. Some of the PCM's can be re-flashed and the VIN's changed, some the VIN is burned into the PCM and that is that. I don't have a way of telling you if you if you can re-flash or not. But if it can be done, it's going to take a DRBIII and not a generic scan tool.

 

[ramenth]

You're not going to like this answer.
Maybe yes, maybe no. You may be able to use a donor PCM, but it will have to be flashed on the car. That's when your going to get your answer.
When the car powers up, there is a handshake protocol.
The PCM wakes up and searches for the body controller and/or the trans controller. The VIN's must match for the system to work. Some of the PCM's can be re-flashed and the VIN's changed, some the VIN is burned into the PCM and that is that. I don't have a way of telling you if you if you can re-flash or not. But if it can be done, it's going to take a DRBIII and not a generic scan tool.

I understand what you're saying about the interface. Especially considering that the PCM is burned with the specific car in mind. Which is what's making me suspicious about what I was told by the other guy. (Let's just say that I've had a long discussion with the same guy over a blower motor resistor and rather it was bad or not...he said it was, when it really was just a loose pigtail.)

I don't think he's taking the TCM and BCM into consideration, especially considering he works for a multi-make dealership and calling him a Chrysler tech is a bit of a stretch. His location sells more imports than domestics.

Then we have to consider the idea of NY state emissions inspection which is a direct link from the DLC to the state's NYVIP which transmits all PCM data to the state data bank. There's no way around it. The state takes that out of the hands of the individual inspector.

Now another question is: if a donor PCM can be used to verify the no start-no spark condition. Will it fire the engine long enough or will there be effects along the CAN setting off codes all through the system, like with the TCM? In other words would I be able to use this as a diagnostic tool long enough for her to be able to get up the money to get it a dealership for a flashable PCM to be installed?

 

[mod38-1]

Make sure you check distributer good. There have been issues with them causing no spark as cam sensor is built into it.

 

[ramenth]

Make sure you check distributer good. There have been issues with them causing no spark as cam sensor is built into it.

Coil took a wipe. Replaced. 8.06V off 8V feed. 11.5V off ASD (which feeds the CPS). Good sensor ground and good ground for the coil, too.

Before it died it was showing a misfire on #3. So while I was in there testing everything and replacing the wiped coil it also saw new plugs, wire, cap, and button. Misfire was diagnosed by someone else, but I didn't see any sense in throwing a new distributor in a car with 106,000 miles when the cap was green and fuzzy. Timing is deadnuts on.

 

[toplscuda]

Raemeth,
Witht he year you have you should not have any issues with swapping a used PCM. There are several guys onthe Sebring Convertible forum who have doen the same thing with success.

 

[ramenth]

Raemeth,
Witht he year you have you should not have any issues with swapping a used PCM. There are several guys onthe Sebring Convertible forum who have doen the same thing with success.

Okay, then. We're going to give it a shot with a used PCM. Found one from a car with Fed emissions from a Cirrus same year, same powertrain. I have a tech with a DRB ready to reflash for me if needed.

 

[gunbunny]

Sorry for the lag in response.
If you use a donor, make sure the P/N's match or supersede one to the other. Either forward or backwards. the P/N should be on a decal on the PCM.
If a donor will work, a flash shouldn't be a problem. You will know very quickly. The PCM won't communicate to the scan tool to preform the flash. If you get communication, you're likely golden.
and by the way, I would have told you to replace the resistor too. That is the usual suspect on 99% of chryslers with no blower motor. But I have seen the pigtails burnt or broken.

 

[ramenth]

Sorry for the lag in response.
If you use a donor, make sure the P/N's match or supersede one to the other. Either forward or backwards. the P/N should be on a decal on the PCM.
If a donor will work, a flash shouldn't be a problem. You will know very quickly. The PCM won't communicate to the scan tool to preform the flash. If you get communication, you're likely golden.
and by the way, I would have told you to replace the resistor too. That is the usual suspect on 99% of chryslers with no blower motor. But I have seen the pigtails burnt or broken.

Thanks, gunbunny. The info I'm finding on here is great on this.

As for the blower motor resistor it wasn't on a Mopar, it was on a Honda and gave more of a GM response in testing. Resistor good, pigtail giving various readings from the same pin. I told the woman GM must have made her Honda. There's a reason the new GM resistors come with a new pigtail. A little contact cleaner, a little dielectric grease, plug in firmly, and her system went to working again. And still is.

But that's the reason we do the full testing isn't it? Don't assume because we've replaced a 100 of 'em that number 1o1 is the exact same thing. TSBs can be handy diag tools and a common fix for a common problem, but I've seen guys rely only on the TSB and wind up not fixing the issue...then wonder why it didn't work.

 

[ramenth]

Over the weekend my buddy tried the PCM on the say so of his "tech" friend. It didn't work.

But...he didn't check part numbers, didn't bother to try to see if his own scanner would communicate and kept going on his ASE Master certified tech's word that it was all a done deal, plug and play. He did it without me being there.

When we had agreed that we would send it over to the dealership so the DRB could be hooked up for reflash.

 

[gunbunny]

I hope he didn't waste his money. There is a reason for different P/N's. The security system is just one factor.
I do hope it works out for him. If not, T.E. Hunt in Schaumburg (spelling) IL can likely repair the old PCM cheaper than a new one. A reman is likely available also. I may have you PM the VIN and I may be able to help with the PCM.

 

[ramenth]

I hope he didn't waste his money. There is a reason for different P/N's. The security system is just one factor.
I do hope it works out for him. If not, T.E. Hunt in Schaumburg (spelling) IL can likely repair the old PCM cheaper than a new one. A reman is likely available also. I may have you PM the VIN and I may be able to help with the PCM.

I'll get it for you.