Circuit/System Testing
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- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B87 Rearview Camera. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- If 10 Ω or greater
- Ignition OFF.
- 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
- Ignition ON.
- Verify a test lamp illuminates between the ignition circuit terminal 6 and ground.
- If the test lamp does not illuminate and the circuit fuse is good
- Ignition OFF.
- Test for less than 2 Ω in the ignition 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 OK and there is voltage at the fuse. Refer to Power Mode Mismatch (With BTM)Power Mode Mismatch (Without BTM) .
- If the test lamp does not illuminate and the circuit fuse is open
- Ignition OFF.
- Test for infinite resistance between the ignition circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, replace the B87 Rearview Camera.
- If the test lamp illuminates
- Engine running, park brake applied, transmission in R.
- Verify a test lamp illuminates between the control circuit terminal 3 and ground.
- If the test lamp does not illuminate
- Ignition OFF, disconnect the X4 harness connector at the X50A Fuse Block - Underhood
- Test for less than 2 Ω in the ignition circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, refer to Backup Lamps Malfunction .
- If the test lamp illuminates
- Ignition OFF, disconnect the X2 harness connector at the K74 Human Machine Interface Control Module, ignition ON.
- Test for less than 1 V between the signal circuit terminals listed below and ground:
- K74 Human Machine Interface Control Module signal (+) circuit terminal 5 X2
- K74 Human Machine Interface Control Module signal (-) circuit terminal 6 X2
- If 1 V or greater
Repair the short to voltage on the circuit.
- If less than 1 V
- Test for infinite resistance between the signal circuit terminals listed below and ground:
- K74 Human Machine Interface Control Module signal (+) circuit terminal 5 X2
- K74 Human Machine Interface Control Module signal (-) circuit terminal 6 X2
- If less than infinite resistance
Repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω between the K74 Human Machine Interface Control Module signal (+) circuit terminal 5 X2 and the B87 Rearview Camera signal (+) circuit terminal 1.
- If 2 Ω or greater
Repair the open/high resistance in the circuit.
- If less than 2 Ω
- If 2 Ω or greater
- Test for less than 2 Ω between the K74 Human Machine Interface Control Module signal (+) circuit terminal 6 X2 and the B87 Rearview Camera signal (+) circuit terminal 4.
- If 2 Ω or greater
Test the signal circuit for an open/high resistance.
- If less than 2 Ω
- If 2 Ω or greater
- Replace the B87 Rearview Camera.
- Engine running, transmission in R.
- Verify a clear rear vision image is displayed on the P17 Info Display Module.
- If a clear rear vision image is not displayed
Replace the K74 Human Machine Interface Control Module.
- If a clear rear vision image is displayed
- If a clear rear vision image is not displayed
- All OK.