I currently have this problem in my 2008 Silverado.... have owned it less than a week with only 19000 miles on it. The door locks go wild locking and unlocking, guages fluctuate, compass display in mirror flashes illegible digits, strange stuff! I had it at the dealer today and they went through the mega fuse / connections (see TSB below). Everything seemed fine then the ghost returned later this evening. Clock reset and guages dropped momentarily.
Did you get a fix for yours?
Here is the tsb that I found online.
#PIT4816: Multiple Electrical Concerns With DTC C0900 - keywords battery c/k cable clock crank cycle door dimming flicker gage gauge gmc hvac inop inoperative instrument ipc lock no panel power radio stall - (Feb 27, 2009)
Multiple Electrical Concerns With DTC C0900
2007 -2009 Cadillac Escalade, ESV, EXT
2007-2009 Chevrolet Avalanche, Silverado, Suburban, Tahoe
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI. Condition/Concern:
Some customer may experience one or all of the following concerns.
1) Intermittent No Crank or No Vehicle Power ( The customer may get the impression that the vehicle actually has a dead battery )
2) Volt gauge fluctuates, and seems to decrease when a high load accessory is turned on ie.. headlamps, wipers
3) IPC backlighting flickers or IPC goes blank
4) Diagnostic Code: B1325 set in several modules followed with a Dtc: C0900 set in the EBCM.
5) Radio clock resets
6) Intermittent Stall
7) Hvac temperature actuator defaults to hot
8) Door locks cycle Recommendation/Instructions:
If you experience one or all of the following concerns and a cause for the concern can't be identified, please check the following items:
1) Remove the 175 amp Mega fuse and inspect for arcing, if any type of arcing is found replace the effected components.
2) When re-installing the 175 amp Mega fuse, torque fasteners that attach the mega fuse to the positive cables to specification in SI.
3) Check the voltage drop reading on the positive and negative battery cables. The voltage drop should be performed with the fuel injectors disabled and while cranking the engine. The voltage drop should not exceed 200 mV. If the voltage drop is above 200 mV, replaced the effected cable.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Your battery needs to be replaced. If your vehicle is under warranty, have the dealer replace the battery. If they say your battery is OK, have them call Pioneer Cherolet and ask for the service department Jason Bales, the number is 1-740-373-9127. Let them know the problem and then let them know you have a friend, Bob Perkins who has a 2008 Chevy crew cab that they fixed by replacing the battery in case they need their memory refreshed. Everything should be back to normal once the battery is replaced. Give me an update after the replacement.
O.K.... here is what I believe to have been my fix (at least for a full week now no issues, several issues a day before this). Before I took the truck back to the dealer, I decided to pull the cables and clean/tighten at all connection points. Did this at the battery and the ground at front of motor. I pulled the fuse box to clean the positive connection on the bottom of the box. After releasing the cam lock handles and raising the box, I noticed an area in the bottom of the box where the plastic looked smashed. There are a lot of guide posts to line up the fuse connectors in the top of the box with the wire harnesses in the bottom portion of the box. In the top of the box, one of these posts was bent over, not going into its sleeve in the bottom but instead smashing into the plastic next to the sleeve (wish I had taken pictures). I fixed this with a pair of pliers, aligned everything and put it all back together and knock on wood, no problem since. I think the connecters from the fuses where not seated good into the harnesses causing the gremlins. If things change I will re-post. Thanks for all the input and suggestions!
had the same problem, also gauges would act all crazy, brought to dealer 4 or 5 times, finally they checked the ignition swith in the column and that was the problem, it was losing voltage, was getting only about 4volts he moved the wires around going to the switch and voltage would come back to 12volts,changed out switch and been fine now for about 6 months, hope this helps
It's been a week now after I got my avalanche back and no problem so far. They never could find the problem. I think when they tightened all the wires and checked the battery cables ect.... They fixed it. I will see for sure in a month if it is really fixed. Will let you know.