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.

Avoid cycling the ignition unnecessarily while the fuse is open. Turning the ignition ON twice with an open fuse results in a 20-40 minute precharge wait time, during which time precharging will be inhibited. It will be necessary to wait until the scan tool Precharge Wait Time parameter counts down to 0 Seconds before continuing with diagnosis.
When the high voltage fuse is open the vehicle will not start.
Test for high voltage interlock circuit operation by lifting up on the high voltage manual disconnect lever to disengage the high voltage interlock circuit. Monitor the high voltage interlock source and return current on the scan tool. High voltage interlock return current should read 0 mA a when the high voltage manual disconnect lever is lifted.
If DTC P0A95 or P0ABC sets when the manual disconnect lever is removed, the high voltage interlock circuit may have a wire to wire short on the high voltage interlock source and return circuits between the X350 and the high voltage manual disconnect lever connector.
If the high voltage fuse opens as soon as the high voltage manual disconnect is installed with the ignition OFF and the high voltage contactors are not stuck closed, the problem is internal to the drive motor generator battery assembly.
If the fuse is open or the high voltage manual disconnect lever is removed, the scan tool parameter will display 0 V for hybrid battery 11.