I had a problem where electrical components just freaked out for no reason. The flashers would go on, the door locks would go up and down, the airbag light would go on, and the fuel pump would go on and off, right when I was going down the road. This is how I seemed to have fixed it.
This is a related GM Service Bulletin:
#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)
Subject: Multiple Electrical Concerns With DTC C0900
Models: 2007 -2009 Cadillac Escalade, ESV, EXT
2007-2009 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2009 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL
(Equipped with Gasoline Engines)
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.
