Circuit/System Testing
WARNING: This page is about a different car, the 2006 Chevrolet Monte Carlo and 2006 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
- With the ignition OFF, disconnect the BCM.
- With the ignition in OFF and ACC, measure for less than 0 volts between the ignition 1 voltage circuit of the BCM connector and ground.
- If over 0 volts, disconnect the ignition switch and check the ignition 1 voltage circuit for short to voltage or short to other ignition switch signal circuit. If the circuit tests normal, test or replace the ignition switch.
- With the ignition in RUN and START, measure for battery voltage between the ignition 1 voltage circuit at the BCM connector and ground.
- If less than battery voltage, disconnect the ignition switch and check the ignition 1 voltage and battery positive voltage circuits for an open or short to ground. If the circuits test normal, test or replace the ignition switch.
- If all circuits test normal, replace the BCM.