Circuit/System Testing

WARNING: This page is about a different car, the 2012 Chevrolet Volt. However, it is still accessible from the selected car via links, so may be relevant.

Vehicle OFF, scan tool disconnected, all doors closed, all accessories OFF, disconnect the harness connector at the A20 radio/HVAC controls. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 5 Ω between the ground circuit terminal 17 and ground.
- If 5 Ω or greater
1. Vehicle OFF.
2. Test for less than 2 Ω in the ground circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, repair the open/high resistance in the ground connection.
- If less than 5 Ω
Vehicle in Service Mode.
Verify the scan tool Hazard Lamps Switch parameter is Inactive.
- If not Inactive
1. Vehicle OFF, disconnect the X2 harness connector at the K9 body control module.
2. Test for infinite resistance between the signal circuit terminal 16 and ground.
  - If less than infinite resistance, repair the short to ground on the circuit.
  - If infinite resistance, replace the K9 body control module.
- If Inactive
Install a 3 A fused jumper wire between the signal circuit terminal 16 and the ground terminal 17.
Verify the scan tool Hazard Lamps Switch parameter is Active.
- If not Active
1. Vehicle OFF, disconnect the X2 harness connector at the K9 body control module, vehicle in Service Mode.
2. Test for less than 1 V between the signal circuit terminal 1 and ground.
  - If 1 V or greater, repair the short to voltage on the circuit.
  - If less than 1 V
3. Test for less than 2 Ω in the signal circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, replace the K9 body control module.
- If Active
Test or replace the A20 radio/HVAC controls.