warriorjoe

I just replaced all the stepper motors in the IPC for my 2003 Silverado. The IPC functions great - all gauges operate as they should. However, I have a parasitic current draw problem I traced to the IPC (my battery kept running down over a period of days). On the bench, the IPC draws about 0.650 amps when ON. After the IGN lead is removed (leaving the BATT lead connected) the total current draw drops to about .350 amps after about 45 seconds. Research indicates this amount of current draw will deplete a battery in about 2 days (that's what happened! I temporarily swapped the IPC with a known good panel and the test panel did not have the current draw problem. The same test with the alternate good panel indicated a quiescent current draw of about 0.012 amps, which should be normal.

QUESTION #1
One option I considered is to connect the BATT lead of the IPC to the IGN lead of the IPC. This way, the only time that current would be supplied at all to the IPC would be when the IGN switch was on. However, I am concerned of the effect this would have on the PCM. I know the PCM sends "go to sleep" signals to many of the devices on the class 2 network. My question is would this cause the PCM to load up with error codes, or not work in some other fashion?

QUESTION #2
Does anyone know the real purpose of there being both a BATT connection AND a IGN connection on the IPC?

QUESTION #3
I am a retired electronics engineer and car hack. If I could get my hands on a schematic of the IPC circuit board, I might be able to fix the problem. I cannot get this info from GM. I wonder if anyone knows of a source for this kind of info?

Thanks for any responses!

Joe

MDTAHOE

I assume you did not have this problem before you messed with the ipc? Why not just replace the ipc and be done with it. They are relatively inexpensive from the dealer (if I remember correctly less than $200) and come pre programmed with correct mileage

warriorjoe

Thanks for your response, MDTAHOE. But you are wrong. The prices I have found for a replacement panel with programming runs at least $450 just for a "rebuilt" one.

No, I did not have the problem before I messed with the IPC. It occurred a few months after that.

The reason I would like to fix it if I can is simply from a personal challenge standpoint.

An additional note I can add for those who are technically inclined is that the high voltage oscillator section of the panel continues to run even after the "IGN" lead is removed, and the Information display gets warm even tho not displaying anything.

As I indicated earlier, the panel gauges, display and lamps all function exactly as they should. It's like the "turn off" command from the PCM does not turn everything off in the panel.

Hopefully someone will respond with some helpful info.

Joe

tech2

any module wake up and sleep functions are usually handled by the gateway module (bcm) not pcm via class 2 serial data line.

The diagrams you require are not available even at the dealership level. The shop diagrams...draw a box and label it ipc and then there are more labelled boxes inside the big box.lol

york electronics handles all the ipc repair in canada, maybe they can source parts for you.

MDTAHOE

Obviously you have not done much research. They are available for around $200 with programming lots of places. At work we get them from the dealer less than 200 programmed. We do get wholesale pricing though.
They are also available from Dorman Products for around $200 programmed. Just google Dorman 2003 Silverado instrument cluster.
There is a core charge which makes it around 400-450 before you give them yours

warriorjoe

Thanks for the info, MDTAHOE. I will probably get one of those $200 Dorman Rebuilt panels if I can't find the solution to this panel soon. You're right, I did not use the keyword "dorman." That brought up the info you mention.

I was hoping someone could answer the question about splicing the BATT lead to the IGN lead in the truck. The panel works OK on the bench that way, but I was not sure if there might not be some other effect I don't know about.

Thanks again.

Joe

MDTAHOE

Unfortunately as tech2 stated that info is not readily available. I doubt anyone here will be able to help you.

warriorjoe

OK. Thanks for the responses, everybody.

I will probably get a rebuilt IPC from NAPA. They sell a rebuilt unit for $199 programmed. I don't know why I did not check them to start with. So used to going to internet for everything. Oh, well. Learn something everyday.

Joe

desrtrat

before you spend any more money, disconnect your negative cable on your battery for a couple of min. a common issue with 02-05 BCM was it would get a brain fart, and not switch off items that needed to be when shut down..this will reset the factory programming..worked on my 03 SS and others.

good luck..

warriorjoe

Thanks, Desrtrat! I will definitely try that.