I have a 2000 C5 corvette. I just changed carpet, cluster, and seats. Old cluster was scratched. When I went to start the car it would just click and not start. Now, if I disconnect the battery for about 30 seconds the car will start right up. After about a minute there is a clicking noise coming from the BCM area and the heat and air control lights and interior lights will flash in tune with the clicking noise, but the car will run fine. If I turn the headlights on and turn the dash dimmer all the way down the clicking will stop and so will the flashing. But after I turn the car off, the car will NOT start back, and the security light in dash will flash. And the clicking noise coming from the bcm area will start again and interior lights will flash. When I try to start it again, either nothing will happen or the starter will bump and immediately stop but not enough to start it. Just a quick bump of the starter is all I get. The car will not restart until after I pull the battery cable back off and wait for atleast 30 seconds. I have only had this car for 3 weeks, and I'm in way over my head on how to fix this. I can't find anyone who even wants to work on it. Any help would be greatly appreciated. Thanks, Jamie

 

Sorry guy, Im not gonna be much help but I think you are on the right track. Im not sure where the mileage resides (in the IPC or the BCM or PCM) but I would bet what you are running into has to do with that type of info. Did you notice is the milage on the car shows on the new cluster? I doubt that you can just swap out the IPC without some procedure to have all the pieces talking to each other.

This post will bump it up to the top, bump it each day.....someone who knows will eventually chime in.

Good luck

If you update your profile, we can see where you live and may be able to point you to a reputable shop in your area.

 

Perfect I will do that. It's reading a lot of loss of communication codes. So something is not communicating right. It showed the mileage for the cluster that I bought, not my original mileage.

 

I thought the cluster and the BCM have to be re'synced with a TECHII to get the mileage correct. Do an "Advanced Search" above if you want to know for sure (or buy a service manual) or put your OLD cluster in to find out!

 

Also, a really good place to post this info would be in the C5 Tech section. Some very knowledgeable people over there. Or try contacting Bill Curlee (forum member) - he knows a lot about the electrical systems in these cars.

 

I have changed the IPC in a 2003 and had no problems. Car started and ran fine. Old cluster had a bad board so i swoped it out and tried it to make sure it ran OK then I had a shop put on the correct no of miles as it is stored in the IPC. Like the others said check with Bill Curlee his is a wizard, and helped me walk through my problems.

 

Sounds to me like you have a bad battery. Just a coincidence that it showed up after changing the cluster.

Take it to Autozone (or somewhere) and have a load test done on it.

GL

 

When the car did this right after changing everything out, I immediately changed it back to the old cluster. It still does the exact same thing. I have already checked the battery and it is fine. I did email Bill but have not heard back from him yet. I just don't know what else to do. Jamie

 

Changing the IPC is just a couple of plug and play connectors IIRC? I have to say it still sounds like classic bad battery symptoms, although the fact it happens when its running suggests power interrupts

All I can suggest is to start at the connections you disturbed and work through methodically. Pay particular attention to the battery terminals and leads.

Could it be that you have a constant drain thats killing the battery? What voltage are you getting across the terminals with your multi meter? 11.6V is discharged.

What codes are you getting?

 

I have traced down everything I have done 5 times over and everything checks out. I will load test the battery tomorrow. I have reset all the codes and these are the ones that now pop up since:

BCM:
B0605
B0502
B0507
B2482
B2587
B2592
B2723

TCS:
C1255
TCS C1255

SCM:
U1255
U1064

RFA:
U1096
U1064
U1016

SBM
U1000
U1040
U1096
U1064

LDCM:
U1064

RDCM:
U1064

PCM: No Codes
IPC: No Codes
Radio: No Codes
HVAC: No Codes

These are all the codes it is reading. I really appreciate all of your help. I am a girl, and I have been around cars all my life and am not car stupid but this one is beyond me. Thanks Jamie.

 

With power issues you'd expect all the U codes as they show that you have a comms issue on the bus.

Try clearing them down and then reproduced the symptoms. Post up what returns. If its a current problem it'll flag as a C (eg B0605C or B0605H). Anything that has cleared will be an H code. The H/C is at the end of the code so you need to post those up too.

Bit worried about the B0605 code. It could suggest the BCM is not well. Its an integrity check of the memory. Hopefully it wasn't damaged when you did the work. Is it "C"; hopefully not?

The B2587 for example could also be a clue. The code sets when the BCM detects an internal malfunction, an open or a short to ground in the column lock drive A circuit or there's an open in the BCM battery positive voltage circuit from BCM2 fuse.

Maybe you disturbed the column lock circuit or pinched a wire?

But rather than guess, try to identify the codes which are current. Once we know we can troubleshoot from the manual.

 

well today I erased and reset all the codes on the car...I then took the car to oreillys to have the battery tested..%t was 12.51 with the key off and 14.10 with the car running. The computer ripple was 6.5mv and it had a good load test.. I then drove the car about 5-10 miles back home and checked the codes..3hese are what I got... PCM- no codes TCS- C1255H BCM- no comm SDM- U1000HC, U1064HC IPC- U1064H, U1176HC, U1160HC RADIO- U1096H, U1064H HVAC- no comm LDCM-U1064H RDCM-U1064H RFA- U1064H I am really dumbfounded on this one...I have sent a message to BILL but I haven't heard back from him yet

 

If it were me, I'd take it back apart to the point you had the IPC removed. Then, I'd clear all the codes, start and drive the car to see if the codes return. I'd expect to see only IPC related codes.

It didn't have this problem prior to replacing the IPC... correct?

SO, logically, someting happenned during the installation of the new IPC.

I'd recommend you re-trace your steps. As someone else pointed out, maybe a wire got pinched or something similar.

 

8VETTE7- I have already followed what BILL said to do in that forum a couple days ago...nothing changed. How do I test to make sure the serial bus connector is working properly

 

trace- I have taken the IPC out twice already looking for any wires or something that could be the culprit..can't find anything...this is so puzzling

 

Jamie, I'll start with a health warning because this one is getting beyond my comfort zone. Hopefully Bill will chime in as he's the guru but I'm tending more towards thinking you have a BCM problem. In my experience the BCM sector of the DIC should say "no codes" if it's clear. The fact it says no comm worries me. You remember I said I was worried before that the BCM may be corrupt in some way. I pulled the procedure for one of your codes (U1000 reproduced below) and that also suggests that it could be no comm with the BCM.

You can reprogram the BCM with a Tech II but smarter guys need to comment before you spend $$ on that avenue.

The SDM is the sensing and diagnostic module associated with the airbag system. Strange that it has so many glitches.

The U1064 and U1160 are often door module related yet the actual modules RDCM and LDCM only show history codes. That tells me its not the modules themselves rather its the communication with the modules. Have you pulled the rubber gaiter in the door and checked the wiring in the door hinge area? It can cause so many random electrical issues if the wires are chafed.

The fact youre getting so many U codes yet the battery is fine makes me think its a communication issue. If the BCM is OK, a connector has to be disturbed or damaged to cause all this. The nightmare scenario is that actually you didn't damage anything at the IPC end but the BCM had a burp about the time you did the work. On the other hand it could just be a bad connector somewhere and reseating/cleaning/changing it will solve the issue.

Heres the procedure for the U1000 current code you have and it points to one (or more) modules not talking to the BCM

DTC U1000 and U1255
Circuit Description

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation when operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the identification number of the module which sent the message. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. When a module does not associate an identification number with at least 1 critical parameter within about 5 seconds of beginning serial data communication, DTC U1000 or U1255 is set. The DTC will only be reported once if more than 1 critical parameter does not have a sending module identification number associated with it.
Conditions for Running the DTC

* Voltage supplied to the module is in the normal operating voltage range.
* Diagnostic trouble codes U1300, U1301 or U1305 are not set.
* The module setting the DTC requires serial data communication to occur.

Conditions for Setting the DTC

At least 1 critical operating parameter has not been associated with an identification number within about 5 seconds after beginning serial data communication.
Action Taken When the DTC Sets

The module uses a default value for the missing parameter.
Conditions for Clearing the DTC

* A current DTC U1000 or U1255 will clear when all critical operating parameter for the module have been associated with an identification number or at the end of the current ignition cycle.
* A history DTC resets after 50 ignition switch cycles with no repeated failure.

Diagnostic Aids

When a malfunction such as an open fuse to a module occurs while modules are communicating, a current DTC is set indicating lost communication with a specific module DTC. When the modules stop communicating, ignition is turned OFF, the current Lost Communication DTC is cleared but the history DTC remains. When the modules begin to communicate again, the module with the open fuse will not be learned by the other modules so DTC U1000 or U1255 is set as current by the other modules. If the malfunction occurs when the modules are not communicating, only DTC U1000 or U1255 is set.
Test Description

The numbers below refer to the step numbers on the diagnostic table.

1.

A Lost Communication with XXX DTC with a history status may indicate the cause of U1000 or U1255.
2.

The modules which is not communicating is the likely cause of U1000 or U1255 being set. The following systems communicate on the class 2 serial data circuit:
* Body Control Module (BCM)
* Electronic Brake Control Module (EBCM)
* Electronic Suspension Control (ESC) Module
* HVAC (with CJ2)
* Sensing and Diagnostic Module (SDM)
* Instrument Panel Cluster (IPC)
* Driver Door Module (DDM)
* Passenger Door Module (PDM)
* Seat Control Module (SCM) (with AAB)
* Powertrain Control Module (PCM)
* Radio
* Remote Control Door Lock Receiver (RCDLR)
5.

The module which was not communicating may have set Lost Communication with XXX DTCs for those modules that it was monitoring.
6.

The module which was not communicating may have set Lost Communication with XXX DTCs for those modules that it was monitoring.
7.

The module which was not communicating may have set Lost Communication with XXX DTCs for those modules that it was monitoring.
11.

The modules which can communicate indicate the module which cannot communicate. You must clear the DTC from these modules to avoid future misdiagnosis.
13.

If all modules are communicating, the module which set U1000 or U1255 may have done so due to some other condition.
14.

The module which set U1000 or U1255 is the likely cause of the malfunction.

 

I was previously told by someone that if the bcm was bad then the car would not crank or start at all. And I can get the car to crank and start I just have to take off the neg battery cable for about 30 seconds...was that person full of crap or is that true?

 

but I'm tending more towards thinking you have a BCM problem

 

Today I put a brand new optima red top battery in the car today and nothing changed. Same symptoms. For the first time today when i was pulling into oreillys to get the new battery my message center read Low Voltage and a couple times now it has said reduce engine power. Do I have to buy a BCM from the dealer or can I buy one offline or from somewhere cheaper? Can I program it myself or do I have to take it to the dealer to have it programmed? I checked with the dealer here and they priced me $1900 alltogether. $1400 for the BCM and $500 for programming it. That seems a little high to me!

 

Hi Jamie

Before you commit mega $$ we need to be sure thats the problem. Could the dealer run any checks to decide if the BCM is good? It could yet be a connection issue and I'd hate for you to spend that kind of $$ on spec and find out the BCM was good.

The reduced power would be the result of low voltage on the system. Have you had the alternator checked. If the battery is good and the alternator has a problem it may be the cause. Start there before the BCM.

I'll check the manual to see if theres anything on that one.