Conditions For Setting DTC
WARNING: This page is about a different car, the 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, 2002 Chevrolet Monte Carlo, and 2002 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
The PCM detects that the heater control circuit current is greater than the capacity of the PCM internal driver for more than 20 seconds.