First real problem
Thread Starter
Drifting
Joined: Jul 2017
Posts: 1,364
Likes: 471
From: S.E. Pennsylvania
First real problem
So I've had my 1998 since 2017 without any major issue. The other day right after I started it I received the "reduced engine power" notification and the engine seemed like it was running on 7 cylinders. The CEL was also on. I turned it off, restarted it and the engine was OK but still had the CEL. I drove it to the store and after restarting it again the CEL was out and the engine was running OK. Then I noticed a whine coming from the engine and the dash and corner lights were cycling. They were normal brightness for about two minutes then dimmed for a second, returning to normal brightness again. This repeated itself as long as the car was running. I drove it home and parked it and just today took it out for a spin and the same issue is happening with the lights cycling and the whining sound. Other than that the car ran as normal. There were no codes, and no further messages from the DIC. I checked the voltage at the battery with the car running and off and it was normal. The generator is two years old and a rebuilt OEM. Thoughts and suggestions please and thanks... 
Administrators: I meant to post this in Tech... sorry...
Administrators: I meant to post this in Tech... sorry...
Last edited by bc6152; Nov 22, 2020 at 01:41 PM.
Melting Slicks
Joined: Nov 2014
Posts: 3,399
Likes: 1,339
From: Havre de Grace Maryland
I am not an expert but I do remember reading similiar problem post with one suggestion was to wiggle the driver's side accordion connector between the door and the body as the issue was happening. If this caused the problem to stop, then the connectors that are in the door accessed by removing the accordion connection need to be fixed. There are post that show how to do this. Hope this helps.
Thread Starter
Drifting
Joined: Jul 2017
Posts: 1,364
Likes: 471
From: S.E. Pennsylvania
Upon doing some further checking after I couldn't unlock the drivers' door, I ran the diagnostics again and came up with the following codes that were all history codes.
LDCM - 2252 - 2204 - 2282 - 2284 - 2262 - 2264 - U1255 - U1064 - U1016 - U1096 - All history codes.
RDCM - 2253 - 2283 - 2285 - 2265 - U1255 - U1064 - U1016 - U1096 - All history codes. As these are all "H" codes do I need to be concerned about any of these?
I looked up the various codes and was flabbergasted at the descriptions of the faults. Loss of communication with PCM and IPC - serial data line malfunction - loss of communication with BCM - key cylinder switch fault - battery #1 and #2 fault. Is it time to sell it?
LDCM - 2252 - 2204 - 2282 - 2284 - 2262 - 2264 - U1255 - U1064 - U1016 - U1096 - All history codes.
RDCM - 2253 - 2283 - 2285 - 2265 - U1255 - U1064 - U1016 - U1096 - All history codes. As these are all "H" codes do I need to be concerned about any of these?
I looked up the various codes and was flabbergasted at the descriptions of the faults. Loss of communication with PCM and IPC - serial data line malfunction - loss of communication with BCM - key cylinder switch fault - battery #1 and #2 fault. Is it time to sell it?
Last edited by bc6152; Nov 22, 2020 at 04:23 PM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,433
Likes: 3,981
From: Cape Coral, Florida
As was previously mentioned this “could” be a serial data bus issue !!...if one of the modules loses either a power or ground that power or ground can find its way onto the serial data wire (pin 2 of the DLC...Data Link Connector) and where you hook up a scan tool too...if power or ground finds its way onto the serial data wire your scan tool can’t communicate with the modules and the modules can’t communicate with one another also..the drivers door module has a connector inside that rubber boot so try shaking the boot a little because you may have a poor connection there...I guess because the driver door is opened and closed a lot those connections go bad over time...sometimes you’ll see the power windows not working or the car may not start and a few other things you may see !!
Last edited by C5 Diag; Nov 22, 2020 at 05:28 PM.
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Thread Starter
Drifting
Joined: Jul 2017
Posts: 1,364
Likes: 471
From: S.E. Pennsylvania
Thread Starter
Drifting
Joined: Jul 2017
Posts: 1,364
Likes: 471
From: S.E. Pennsylvania
I pulled the boot off and inspected the connectors inside. I did not find any malformed metal connector parts and the connection was tight. The whine I hear is not from the alternator but it actually sounds like it's behind the driver's seat. I even checked the receiver to see it was making noise as it's right behind the seat under the tonneau cover but nada... As I previously stated the whine is cyclical and after each cycle of about two minutes the lights dim for a half second then the cycle repeats itself. I let it run for about 15 minutes and it just continued.
The historical codes pulled indicate a serial data issue but tracking it beyond what I've already tried is not possible for me. Could it be the fuel pump?
Thanks for the assistance and hope all have a safe and happy Thanksgiving day.
The historical codes pulled indicate a serial data issue but tracking it beyond what I've already tried is not possible for me. Could it be the fuel pump?
Thanks for the assistance and hope all have a safe and happy Thanksgiving day.
Instructor
Joined: Mar 2012
Posts: 156
Likes: 19
From: Reading Pennsylvania
I can't help you with your wiring issue, but I also have a whining noise behind the seat especially when I have less than 1/2 tank of gas. I remember a Bill Curlee post that said some fuel pumps are noisy, some are quiet.
