Circuit/System Testing

IMPORTANT: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

Inspect the Ign Switch fuse for open. The fuse should be OK.
- If the fuse is open, test the following circuits for a short to ground, if all circuits test OK, replace the BCM.
  - Battery positive voltage of the ignition switch
  - Accessory voltage
  - Off/Run crank voltage
  - Ignition 1 voltage
Disconnect the ignition switch connector.
Test for battery positive voltage between the battery positive voltage circuit of the ignition switch and ground.
- If less than battery positive voltage, repair the circuit for an open/high resistance

IMPORTANT: The ignition switch component test must be preformed before proceeding with this test to verify the integrity of the switch.

Perform the ignition switch component test.
- If the ignition switch fails, replace the ignition switch.
Ignition OFF, disconnect BCM connector C1, test for less than 1 volt between the following circuits of the BCM and ground.
Ignition key out, test for less than 1 volt between the following circuits of the BCM and ground.
- Ignition key resistor signal
- Off/Run crank
- Accessory voltage
- Ignition 1 voltage
- If more than 1 volt, repair the circuit for a short to voltage.
Test for less than 1 ohm of resistance between the BCM and the ignition switch on the following circuits.
- Ignition key resistor signal
- Off/Run crank
- Accessory voltage
- Ignition 1 voltage
- If greater than 5 ohms, repair the circuit for open/high resistance
Test for infinite resistance between the ignition key resistor signal circuit of the BCM and ground.
- If less than infinite resistance, repair the signal circuit for a short to ground.
Replace the BCM.