Conditions for Setting the DTC

WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

P0C77

One of the following conditions exist:

The high voltage DC current is greater than 25 A during precharge.
Within 20 milliseconds of the start of precharge, hybrid battery calculated voltage and powertrain inverter module terminal voltage are already within 23 V of each other.

P1A20

140 milliseconds after the start of precharge, hybrid battery calculated voltage and hybrid battery terminal voltage are 23 V apart.