Circuit/System Testing

Inside Rearview Mirror DimmingMalfunction

NOTE:

It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off
2. Disconnect the electrical connector:A10 Inside Rearview Mirror
3. Test for less than 10 ohms between the test points:Ground circuit terminal 5 & Ground
   • If 10 ohms or greater 
   1. Disconnect the ground connection:
   2. Test for less than 2 ohms between the test points:Ground circuit terminal 5 & The other end of the circuit@GroundTerminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
   • Go to next step: If less than 10 ohms 

1. Ignition - On / Vehicle - In Service Mode
2. Verify a test lamp turns On between the test points:Ignition circuit terminal 2 & Ground
   • If the test lamp does not turn On and the circuit fuse is OK 
   1. Ignition/Vehicle - Off & Remove - Test lamp
   2. Test for less than 2 ohms between the test points:Ignition circuit terminal 2 & Output terminal@FuseF27UA 10A Fuse
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Verify the fuse is OK and there is voltage at the fuse.
   • If the test lamp does not turn On and the circuit fuse is open 
   1. Ignition/Vehicle - Off & Remove - Test lamp
   2. Test for infinite resistance between the test points:Ignition circuit terminal 2 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:A10 Inside Rearview Mirror
   • Go to next step: If the test lamp turns On 
3. Test or replace the component:A10 Inside Rearview Mirror

Day/Night StatusMalfunction

NOTE:

It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off
2. Disconnect the electrical connector:A10 Inside Rearview Mirror
3. Connect a test lamp between the test points:Control circuit terminal 1 & Ground
4. Ignition - On / Vehicle - In Service Mode
5. Perform the scan tool control function:Backup Lamp - Active & Inactive

   Verify the test lamp turns On and Off.

   • If the test lamp is always Off 
   1. Ignition/Vehicle - Off & Remove - Test lamp
   2. Disconnect the electrical connector:K9 Body Control Module
   3. Test for infinite resistance between the test points:Control circuit terminal 1 @Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
   4. Test for less than 2 ohms between the test points:Control circuit terminal 1@Component harness & The other end of the circuit@GroundTerminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Refer to:Backup Lamps Malfunction
   • If the test lamp is always On 
   1. Ignition/Vehicle - Off & Remove - Test lamp
   2. Disconnect the electrical connector:K9 Body Control Module
   3. Ignition - On / Vehicle - In Service Mode
   4. Test for less than 1 V between the test points:Control circuit terminal 1@Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 VRefer to:Backup Lamps Malfunction
   • Go to next step: If the test lamp turns On and Off 
6. Test or replace the component:A10 Inside Rearview Mirror