Circuit/System Testing

Trunk Release Switch Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the X920 inline harness connector at the S58A Rear Compartment Lid Unlatch Switch-Exterior. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 Ω between the ground circuit terminal 3 and ground.
   • If 10 Ω or greater 
   1. Ignition 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 10 Ω 
3. Ignition ON.
4. Verify the scan tool Trunk Lid/Liftgate Window Exterior Unlatch Switch parameter is Inactive.
   • If not Inactive 
   1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
   2. Test for infinite resistance between the signal circuit terminal 4 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 
5. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 3.
6. Verify the scan tool Trunk Lid/Liftgate Window Exterior Unlatch Switch parameter is Active.
   • If not Active 
   1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
   2. Test for less than 1 V between the signal circuit 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 
7. Test or replace the S58A Rear Compartment Lid Unlatch Switch-Exterior.

Release Actuator Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the KR95B Rear Compartment Lid Unlatch Relay. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 Ω between the ground circuit terminal 3 and ground.
   • If 10 Ω or greater 
   1. Ignition 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 10 Ω 
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 5 and ground.
   • If the test lamp does not illuminate and the circuit fuse is good 
   1. Ignition OFF.
   2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
   • If the test lamp does not illuminate and the circuit fuse is open 
   1. Ignition OFF.
   2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance,
   3. Disconnect the harness connector at the M40 Rear Compartment Lid Latch.
   4. Test for infinite resistance between the control circuit terminal 1 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the KR95B Rear Compartment Lid Unlatch Relay
   • If the test lamp illuminates 
5. Connect a test lamp between the control circuit terminal 1 and the ground circuit terminal 3.
6. Verify the test lamp briefly turns ON when commanding the Trunk Lid Unlatch with a scan tool.
   • If the test lamp is always OFF 
   1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
   2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
   3. Test for less than 2 Ω in the control 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 the test lamp is always ON 
   1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
   2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K9 Body Control Module.
   • If the test lamp turns ON and OFF 
7. Verify that a test lamp does not illuminate between the control circuit terminal 4 and ground.
   • If the test lamp illuminates 

     Repair the short to voltage on the control circuit

   • If the test lamp does not illuminate 
8. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M40 Rear Compartment Lid Latch. It may take up to 2 minutes for all vehicle systems to power down.
9. Test for less than 10 Ω between the ground circuit terminal 2 and ground.
   • If 10 Ω or greater 
   1. Ignition 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 10 Ω 
10. Connect the harness connector at the M40 Rear Compartment Lid Latch
11. Ignition ON, connect a 10 A fused jumper wire between the B+ circuit terminal 5 and the control circuit terminal 4.
12. Verify the M40 Rear Compartment Lid Latch is activated.
    • If the M40 Rear Compartment Lid Latch does not activate 
    1. Ignition OFF, disconnect the harness connector at the M40 Rear Compartment Lid Latch.
    2. Test for less than 2 Ω in the control circuit end to end.
       • If 2 Ω or greater, repair the open/high resistance in the circuit.
       • If less than 2 Ω, replace the M40 Rear Compartment Lid Latch.
    • If the M40 Rear Compartment Lid Latch activates 
13. Test or replace the KR95B Rear Compartment Lid Unlatch Relay.