Gremlin King Defeated....I think. (Long)
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There was a point when the car started doing everything at the same time. All the DIC/IPC lights would come on in random sequence, chimes playing, then this crazy "quivering" of the tach and speedo. One time, on the freeway it also did the IPC "sweep" that it does at startup......as if all power had momentarily been cut, then restored or the ignition switch turned. With that, within a few seconds it would sputter for a second or two then pick up again and run fine. Lastly, it would continuously unlock/lock the doors while driving down the street! How irritating is that?
Bill felt it was in the ignition somewhere. I had started with the unsuccessful repair of my ignition switch and then replaced it with a new one. This did not seem to have any impact. Then Bill suggested the anti theft system. We reset a few things and the crazy "sweeps" disappeared. Everything else remains thus far. Cleaning the BCM seemed to help....I could go longer intervals between code mayhem (20 mins vs 5) but when they returned they were ALWAYS the same codes from same modules and the ABS/TC DIC warnings. All U codes and all will be U1016 and U1096 which is loss of com with PCM and IPC respectively. So, that's the run down refresher.
Bill felt it was in the ignition somewhere. I had started with the unsuccessful repair of my ignition switch and then replaced it with a new one. This did not seem to have any impact. Then Bill suggested the anti theft system. We reset a few things and the crazy "sweeps" disappeared. Everything else remains thus far. Cleaning the BCM seemed to help....I could go longer intervals between code mayhem (20 mins vs 5) but when they returned they were ALWAYS the same codes from same modules and the ABS/TC DIC warnings. All U codes and all will be U1016 and U1096 which is loss of com with PCM and IPC respectively. So, that's the run down refresher.
Did you get a chance to see if the two connectors that plug into the switch have any damaged/bent female pins??
If that doesnt prove out,, pull the jumper clips off both STAR connectors and jump the BCM, PCM and IPC terminals together on the STAR connector with the most wires.
That will isolate the star connectors of all the other modules
Race Director
Joined: May 2012
Posts: 15,768
Likes: 3,283
From: Phoenix area, AZ
Im going to post the DTC reference info from the service manual.
Does your DRLs function properly for both sides as a DRL and a blinker when you turn the blinker on??
There are TWO relays involved in the circuit, two light bulbs the multifunction switch and the BCM its self and a few ground connectors.
Has your BCM ot the passengers footwell ever been wet???
Bill
Does your DRLs function properly for both sides as a DRL and a blinker when you turn the blinker on??
There are TWO relays involved in the circuit, two light bulbs the multifunction switch and the BCM its self and a few ground connectors.
Has your BCM ot the passengers footwell ever been wet???
Bill
The rest of the diagnostics I don't think I can do. I don't have a scan tool or test lamp, much less know how to use either. Electrical just isn't my forte. I'll keep an eye on things after I replace the hazard switch to see if they reappear and just take it from there. Thanks for the assistance.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If it were me,, i would male sure that both bulbs and bulb sockets are in pristene shape. Make sure that the electrical contacts are clean and tight and not corroded.
Pull the relays and make sure that there is no corrosionon the spade contacts.
Give that simple stuff a try before you replace stuff.
Pull the relays and make sure that there is no corrosionon the spade contacts.
Give that simple stuff a try before you replace stuff.
Race Director
Joined: May 2012
Posts: 15,768
Likes: 3,283
From: Phoenix area, AZ
If it were me,, i would male sure that both bulbs and bulb sockets are in pristene shape. Make sure that the electrical contacts are clean and tight and not corroded.
Pull the relays and make sure that there is no corrosionon the spade contacts.
Give that simple stuff a try before you replace stuff.
Pull the relays and make sure that there is no corrosionon the spade contacts.
Give that simple stuff a try before you replace stuff.
Thread Starter
Racer
Joined: Aug 2002
Posts: 369
Likes: 11
From: NV
Update
I have been isolating modules one by one but have not yet been able to review the data yet. I have noticed several interesting tidbits that may help in finally solving this issue:
The SECURITY light tends to illuminate time to time, usually with the other lights of the dash. It has become more frequent and now on its own. It does not seem to relate to any other problem. It is programmed by the PCM and BCM. Perhaps another piece of information to help solve the issue.
The bouncing tach persists. Engine on, idling the needle bounces without even touching the gas. Engine off, accessory on ignition....if I push gas pedal the tach will bounce up and again letting off pedal. But with it now I get a DIC message "Charge System fault" and I can hear a smooth grinding at the throttle body solenoid and a click. Is this normal? Each time I press the gas pedal it happens. If I switch ignition on and off, it may disappear but often comes back....but only with "charge system fault".
I welcome your comments.....
The SECURITY light tends to illuminate time to time, usually with the other lights of the dash. It has become more frequent and now on its own. It does not seem to relate to any other problem. It is programmed by the PCM and BCM. Perhaps another piece of information to help solve the issue.
The bouncing tach persists. Engine on, idling the needle bounces without even touching the gas. Engine off, accessory on ignition....if I push gas pedal the tach will bounce up and again letting off pedal. But with it now I get a DIC message "Charge System fault" and I can hear a smooth grinding at the throttle body solenoid and a click. Is this normal? Each time I press the gas pedal it happens. If I switch ignition on and off, it may disappear but often comes back....but only with "charge system fault".
I welcome your comments.....
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Thread Starter
Racer
Joined: Aug 2002
Posts: 369
Likes: 11
From: NV
UPDATE
Finally bit the bullet and replaced TAC module. Result was exact same codes, lights and alarms.......so I think that effectively rules that out.
I have traced all of the codes, alarms, lights and DIC warnings and they all seem to be ultimately PCM controlled.....this suggests to me that the PCM is the culprit. In addition the tach and speedo sensors are PCM controlled. This has to be the issue.
New gremlins include the HVAC lights, door switch illumination and front driving lights all cycling on and off randomly.
Will let you know........wish me luck.
Finally bit the bullet and replaced TAC module. Result was exact same codes, lights and alarms.......so I think that effectively rules that out.
I have traced all of the codes, alarms, lights and DIC warnings and they all seem to be ultimately PCM controlled.....this suggests to me that the PCM is the culprit. In addition the tach and speedo sensors are PCM controlled. This has to be the issue.
New gremlins include the HVAC lights, door switch illumination and front driving lights all cycling on and off randomly.
Will let you know........wish me luck.