Circuit/System Testing

Single Outside Mirror Defogger Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 and X2 harness connectors at the appropriate E17 Outside Rearview Mirror Glass. 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 1 X2 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. Engine running, connect a test lamp between the control circuit terminal 1 X1 and the ground circuit terminal 1 X2.
4. Verify the test lamp turns ON when commanding the Rear Defogger On with a scan tool.
   • If the test lamp is always OFF 
   1. Ignition OFF, remove the test lamp, disconnect the X3 harness connector at the X53A Fuse Block - Rear Body.
   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 X53A Fuse Block - Rear Body.
   • If the test lamp turns ON 
5. Test or replace the E17 Outside Rearview Mirror Glass.

Both Outside Mirror Defogger Malfunction

1. Ignition OFF, disconnect the KR5 Rear Defogger Relay, ignition ON
2. Verify that a test lamp does not illuminate between the control circuit terminal 87B and ground.
   • If the test lamp illuminates 

     Repair the short to voltage on the control circuit.

   • If the test lamp does not illuminate 
3. Ignition ON, connect a 10 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87B.
4. Verify the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm.
   • If the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger do not become warm 
   1. Ignition OFF, remove the jumper wire, disconnect the X1 harness connector at the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger.
   2. Test for infinite resistance between each 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 E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger.
   • If the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm 
5. Test or replace the KR5 Rear Defogger Relay.