Diagnostic Aids
WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
If the high voltage contactors opened while under high current load, replace BOTH high voltage contactors. The following conditions could cause the high voltage contactors to open while under high current load:
- A collision resulting in supplemental inflatable restraint (SIR) deployment.
- A collision that activates the high voltage circuit impact detection (HVCID) sensor.
- A high voltage circuit impact detection sensor circuit fault that occurs while the vehicle is moving.
- A loss of power or ground to the drive motor generator battery control module while the vehicle is moving.
The precharge time can be affected by the following:
- A long precharge time may be caused by an open 125 A fuse in the manual disconnect lever
- A short precharge time may be caused by a positive high voltage contactor stuck.
- A negative high voltage contactor stuck closed will not affect the precharge sequence.
A long or short precharge time may cause any of the following;
The drive motor generator battery control module will start a precharge wait timer after failing 2 consecutive precharge events. The contactors will not close until the precharge wait time has timed out.