Set Conditions
WARNING: This page is about a different car, the 1999 Buick Regal and 1999 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
DTC C1242 will set when system voltage is greater than 8 volts and pump motor is commanded OFF. A DTC exists if the voltage across the pump motor is between 3.3 and 5.2 volts for 2.0 seconds.