[Stylemaster47]

My wife's 2003 PT Turbo went into "limp mode" this afternoon on her way home. It has 125,000 miles, and I replaced the ECM in June of 2015 (and the timing belt before that and the turbo a year ago). Of course I purchased the 2-Year warranty on the ECM! Thursday night I was backing it out of the garage and the oil light came on. I checked the code with the Key Dance and sure enough, code P0522 ; Oil Pressure Unit low voltage. So I cleaned the connector with Contact Cleaner, hooked it back up, disconnected the battery to clear the codes. Started her up, ran fine. We have driven the car probably 50 miles since then.

This afternoon, she said it began to drive "funny" and it didn't sound normal (she knows her car well!). It had little power, would not change from 2nd gear and the Check Engine light came on, then the Oil Light. She was able to get it in a parking lot. I performed the Key Dance and pulled P1603, which as near as I can tell, is PCM Internal Dual Port RAM Communications Failure. It is odd that the P0552 didn't register this time.

I had a front wheel bearing replaced at a local shop recently, but that is the only repairs that have been performed by someone other than me. It has been running fine since the ECM was replaced 3 years ago, EXCEPT one instance on the freeway, in the summer heat here in SC, running about 80 mph, when there was a slight hiccup. It was like the engine and all electrical died - for about 1/10 of a second - just a snap of a finger.

So...I am leaning towards another Rebuilt ECM. I purchased this one from Imperial Car Computer Exchange in Cary NC, and feel that the Under hood Heat killed another one. Thoughts? Any additional sources for these ECM units? I truly appreciate any and all input!

 

[Doug D]

I would check and clean the connections and thoroughly check the wiring harness before condemning the ECM. You want to rule out all other possible issues before replacing the ECM.

 

[chuzz]

You might also want to check the ground wires on the inside of the driver side fender. This is a known problem area of the PT's. Remove the air box in order to get a good look. And don't just look at the wires, grab them and shake them. Sometimes the corrosion won't be visible but if you grab the wires, they'll break in your hand. If not that, then check and make sure your cooling fans are both working properly too. Unfortunately for you, the 03 is a one year only model setup and the replacements are NOT cheap. If you can find one.

 

[Turbotangerine]

I have seen cam sensors pull the 5v reference down causing a stall condition. there is also a intermediate connector under the intake I have seen issues with too. o2 sensors have been know to cause weird running issue on the PT. Mine was getting 14 mpg when I first got it. I put some 3.6l pentastart o2's in it and now I get close to 19 in city driving.

 

[aussiecruiser]

You might also want to check the ground wires on the inside of the driver side fender. This is a known problem area of the PT's. Remove the air box in order to get a good look. And don't just look at the wires, grab them and shake them. Sometimes the corrosion won't be visible but if you grab the wires, they'll break in your hand. If not that, then check and make sure your cooling fans are both working properly too. Unfortunately for you, the 03 is a one year only model setup and the replacements are NOT cheap. If you can find one.

Not sure you are on here anymore after such a long time but can you clarify the reference to the cooling fan please?
I'm having the dreaded 32 and 37 O2 error codes and am on the verge of buying a reman ECM from CarComputerExchange (but) recently I found someone (previous owner maybe) had done some suspicious mods to the wiring look for the cooling fan which I have reconnected as per the manufacturers wiring diagram. The car runs at normal operating temperature but your comment has me very very curious.
cheers
David
'05 2.4 Limited, Autostick
Australia

 

[aussiecruiser]

Not sure you are on here anymore after such a long time but can you clarify the reference to the cooling fan please?
I'm having the dreaded 32 and 37 O2 error codes and am on the verge of buying a reman ECM from CarComputerExchange (but) recently I found someone (previous owner maybe) had done some suspicious mods to the wiring look for the cooling fan which I have reconnected as per the manufacturers wiring diagram. The car runs at normal operating temperature but your comment has me very very curious.
cheers
David
'05 2.4 Limited, Autostick
Australia

Just a follow up from above.
Today I started the car for the first time in a week (after clearing the codes and leaving it with the + and - cables clamped together after disconnecting the battery for all that time) and no error codes which is what I expected so I left it running and waited for it to reach operating temperature in my driveway.
Making a mental note that I had never heard the cooling fans fire up (which you don't really while driving the car) I sat and waited. The car came to operating tepmperaure and all was going well so I waited...and waited....and then "Bong" the chime chimed and the Mil light came on.....all at the same time the cooling fans fired up.!!!!
Another curiosity. GGRR.

 

[chuzz]

When you first start the car and turn on the a/c, the low speed fan should come on within 5-10 seconds. It doesn't matter what the air temp outside is. If it's not coming on fairly quickly, you really need to check the wiring and connections to the fans. It sounds like the high speed fan is operating properly once the car is up to operating temp. Of course, I don't even know if you have a/c in your PT. You could always direct wire each fan from the battery just to check and make sure they both work. If so, then you know it's either a wiring issue or perhaps a defective relay. Fortunately, the relays under the hood are the same number, so you can swap some around to check them.

 

[Scrounge]

My '92 Dakota had similar hiccups before I sold it. They can be caused by the cam sensor (which I replaced), the crank sensor, or the distributor. Or a frayed wire.

Its computer was also replaced. The screw (or small bolt) hole kept coming loose; eventually, I epoxied it back into place. Also, one of the plastic snaps where the wiring harness connects was missing, so I had to keep pushing it back on whenever I opened the hood.

 

[aussiecruiser]

When you first start the car and turn on the a/c, the low speed fan should come on within 5-10 seconds. It doesn't matter what the air temp outside is. If it's not coming on fairly quickly, you really need to check the wiring and connections to the fans. It sounds like the high speed fan is operating properly once the car is up to operating temp. Of course, I don't even know if you have a/c in your PT. You could always direct wire each fan from the battery just to check and make sure they both work. If so, then you know it's either a wiring issue or perhaps a defective relay. Fortunately, the relays under the hood are the same number, so you can swap some around to check them.

Yes thanks man, I discovered that after I posted and found some good YouTube videos about faulty PT cooling fans and one was for a PT that had a problem with the MIL light coming on due to that. Then found reference in some service notes from Chrysler giving all the actual faults that can create a MIL light and give the error as O2 faults one being bad readings from cooling fans. (What a joke that is)
About a months ago while under the car changing yet again the downstream O2 sensor I happened to notice somebody had been playing with the cooling fan wiring. They had cut off the wire to the Low Speed and spliced it into the High Speed wire. I then replaced the original setup but didn't know if anything really happened or why it had been fiddled with in the first lace. Now thanks to Chuzz I have determined that the Low speed part of the fan motor is not functioning because it does not operate once I turn on the A/C. I should note that when the light came on yesterday the exact same moment the high speed fan kicked in, the A/C was on as I was trying to "induce" the fans to work.
That said I have now ordered a new complete fan assembly.
By the way ALL Aussie sold PT's have A/C.
I'll post results next week when I have the new fan installed.

 

[chuzz]

Good luck with it aussiecruiser. These can be very frustrating cars to work on. But they seem to have a cult type following. If I had the money, I'd go grab an 05 Convertible Turbo 5-speed that's for sale about 20 miles away from me. Needs a good cleaning, but is in overall pretty decent shape.

 

[aussiecruiser]

Well amazingly quick supply of the new cooling fan assembly which I fitted today.
I was totally overjoyed as the new one does everything it is supposed to do and for the first time since I bought this car I was able to stand and watch as the cooling fans came on as required, and yes when I cycled the Aircon the low fan came on as it should.
I let the car sit running in my driveway for maybe 30 - 40 minutes and then took it for a drive...all good and perfect operation.....
Turned it off for 15 minutes and restarted it and still all good....left it running while I tidied up my toolbox ready to go for a long run feeling really good....
Got into the car and straight away realised that the MIL light was back on with the dreaded 32 and 37 codes.

I just don't know where to go from here as I have contacted 3 suppliers of so-called reman unit in US to ask specific questions before I place an online order and not a single one had bothered to reply.
So that's another $250 spend for what in reality is no further progress.

 

[Junkman George]

Did you check your grounds left front wheel inner fender?
These vehicles are, well, strange. They have to have really good battery connections, and follow the - battery wire back to where it grounds at a bolt. In the area there are two bundles of ground wires bolted down. The plan, when these were built, was to ram a bolt through a serrated cable end into a hole with an air gun, hoping the serrations would break the paint enough to ground the whole vehicle. Maybe good at the time, but these give troubles anytime after 5 years, depending on your climate.
Remove the - battery terminal, take the bolts out, clean the lugs, remove some paint, and bolt the lugs back down. Grease the area to prevent future problems.
The large bundles of wires in crimp cable ends give troubles too, but if your climate is dry, and you are far from salt water, I can't really suggest hacking up your wiring harness on a whim. I like to see an indication, like lost ground at the front turn signal lights, or rad fan malfunction.

 

[aussiecruiser]

Did you check your grounds left front wheel inner fender?
These vehicles are, well, strange. They have to have really good battery connections, and follow the - battery wire back to where it grounds at a bolt. In the area there are two bundles of ground wires bolted down. The plan, when these were built, was to ram a bolt through a serrated cable end into a hole with an air gun, hoping the serrations would break the paint enough to ground the whole vehicle. Maybe good at the time, but these give troubles anytime after 5 years, depending on your climate.
Remove the - battery terminal, take the bolts out, clean the lugs, remove some paint, and bolt the lugs back down. Grease the area to prevent future problems.
The large bundles of wires in crimp cable ends give troubles too, but if your climate is dry, and you are far from salt water, I can't really suggest hacking up your wiring harness on a whim. I like to see an indication, like lost ground at the front turn signal lights, or rad fan malfunction.

Yes my friend I have checked all that. Even ground the paint off the body at that point because, as you say, the serrations on the washer didn't really break through the paintwork. Cleaned all bolts, washers, everything but have to say the vehicle appears to have been garaged all its life because corrosion is not-existant.
I'm going back towards the view held by many that the EMU gets a bit silly when the heat build in the engine bay. On reflection over the days events I realised that all the time the car was running in my driveway the hood was open and it was only when I took it for a spin that the hood was closed allowing heat build-up. (that said the ambient temperature at the time was about 10c (50F to you guys lol). I left the car sitting with the hood open afterwards for about an hour, cleared the codes and fired it up...and no MIL light because by then everything was cold again.

Tomorrow morning I'm going to try one more thing. I have now removed the rubber hood seals along the front and rear of the engine bay which at road speed will allow cold air to swirl through the engine bay. The weather forecast tomorrow is for a maximum of 14c ( 57F) and I'm curious about how far I can drive until the MIL light returns.
This is because if I am ever going to get the car road approved I need the light to stay out while the tester does his thing. If it does I will be certified as road legal and at least pay my fees and use the car legally on the road. Once that is achieved the car will not be retested ever as long as I remain the current owner.
Desperate times means desperate measures lol

 

[chuzz]

Have you tried clearing the codes with a code scanner? I know that's a stupid question, but I'm just the guy to ask it. If not, then try that. If so, maybe it has to have so many drive cycles before they clear. IDK Sometimes I miss the old days of the cars that DIDN'T have any computer controls.

 

[chuzz]

Hey Aussiecruiser, I've sent a PM to a contact on the ptcruiserlinks forum about your situation. He rebuilds and programs PCM's for the PT's and NOBODY has ever complained about his work there. I've asked him to look at your situation and see what he thinks. I hope you don't mind.

 

[Junkman George]

Yes my friend I have checked all that. Even ground the paint off the body at that point because, as you say, the serrations on the washer didn't really break through the paintwork. Cleaned all bolts, washers, everything but have to say the vehicle appears to have been garaged all its life because corrosion is not-existant.
I'm going back towards the view held by many that the EMU gets a bit silly when the heat build in the engine bay. On reflection over the days events I realised that all the time the car was running in my driveway the hood was open and it was only when I took it for a spin that the hood was closed allowing heat build-up. (that said the ambient temperature at the time was about 10c (50F to you guys lol). I left the car sitting with the hood open afterwards for about an hour, cleared the codes and fired it up...and no MIL light because by then everything was cold again.

Tomorrow morning I'm going to try one more thing. I have now removed the rubber hood seals along the front and rear of the engine bay which at road speed will allow cold air to swirl through the engine bay. The weather forecast tomorrow is for a maximum of 14c ( 57F) and I'm curious about how far I can drive until the MIL light returns.
This is because if I am ever going to get the car road approved I need the light to stay out while the tester does his thing. If it does I will be certified as road legal and at least pay my fees and use the car legally on the road. Once that is achieved the car will not be retested ever as long as I remain the current owner.
Desperate times means desperate measures lol

You could pull the cluster and remove the bulb = no light. Put it back later.
Locally I have been able to buy used PCMs for $50-$75 in junkyards 50/50 chance.
I've been working on a mystery magical tour Nitro here and hope to get out for a road test this afternoon.

 

[Bob Lincoln]

Clearing codes doesn't work, as it will indicate that the codes have been cleared, and they won't pass you until it's had a certain number of start and drive cycles.
Removing the light does nothing to hide the codes from a scan tool, which is what they use in MA and probably most places.

 

[valiant67]

The only thing clearing codes may do is tell you if the code comes back immediately or only comes back after a certain time which might help with diagnostics.

 

[Doug D]

To add to Bob's post, whatever scanner/reader is used, it will tell them if all components are in "ready" status. If not, a certain amount of trip cycles have to be completed before they will be in "Ready" status.

 

[ImperialCrown]

It depends upon the Australian emissions test. Do they check the OBDII monitors or is it simply a Ck eng light check? If the light doesn't come on at key-on for a bulb-check, it still may fail the vehicle inspection requirements.
What is your Chrysler PCM part number on the label?
PCM rebuilders/vendors in the USA would probably not have access to Export emission market PCMs.