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.

The engine harness connector for the auxiliary transmission fluid pump control module and the mating connector for the transmission auxiliary pump motor can be improperly connected to each other. All of the following conditions may be observed if the improper connectors are mated together:

DTC P0C2B
The TRANS PUMP 60A fuse will open
BCM DTC B1433
Air conditioning system does not blow cold air

The auxiliary transmission fluid pump control module monitors the status of the auxiliary transmission fluid motor/pump as well as its own internal circuitry. This control module does not store its own diagnostic status. Diagnostic status for the current ignition cycle is reported to the hybrid powertrain control module. The diagnostic status within the auxiliary transmission fluid pump control module is reset at every ignition-off cycle.

To determine if a fault is present, while commanding the aux. trans. fluid pump speed to 50 percent observe the hybrid powertrain control module Aux. Trans. Fluid Pump Fault Status 1 and the hybrid powertrain control module Aux. Trans. Fluid Pump Fault Status 2 parameters. Both readings should display No Fault.

Below is the fault status that will be reported if a fault condition is current.

No PWM Response

This fault status indicates the hybrid powertrain control module does not detect the automatic transmission auxiliary fluid pump Control Feedback circuit signal.