Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing
Only one camera image distorted
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate 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, replace the K157 Video Processing Control Module.
- If less than 10 Ω
- Ignition ON.
- Test for 4.8-5.2 V between the 5 V reference circuit terminal 6 and ground.
- If less than 4.8 V
- Ignition OFF, disconnect the harness connector at the K157 Video Processing Control Module.
- Test for infinite resistance between the 5 V reference circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the 5 V reference circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K157 Video Processing Control Module.
- If greater than 5.2 V
- Ignition OFF, disconnect the harness connector at the K157 Video Processing Control Module, ignition ON.
- Test for less than 1 V between the 5 V reference circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K157 Video Processing Control Module.
- If between 4.8-5.2 V
- Ignition ON.
- Test for less than 10 V between the signal circuit terminals listed below and ground:
- Vision Signal + signal circuit terminal 1
- Vision Signal - signal circuit terminal 4
- If 10 V or greater
- Ignition OFF, disconnect the X1 harness connector at the K157 Video Processing Control Module, ignition ON.
- 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, replace the K157 Video Processing Control Module.
- If less than 10 V
- Ignition OFF.
- Test for infinite resistance between the signal circuit terminals listed below and ground:
- Vision Signal + signal circuit terminal 1
- Vision Signal - signal circuit terminal 4
- If less than infinite resistance
- Disconnect the X1 harness connector at the K157 Video Processing Control Module.
- Test for infinite between the signal circuit and ground.
- If less than infinite resistance, repair the short to voltage on the circuit.
- If infinite resistance, replace the K157 Video Processing Control Module.
- If infinite resistance
- Test for less than 2 Ω between the appropriate video signal circuit terminals listed below:
- B174G Frontview Camera - Grille video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 1 X1
- B174G Frontview Camera - Grille video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 11 X1
- B87 Rearview Camera video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 4 X1
- B87 Rearview Camera video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 14 X1
- B225L Sideview Camera - Left video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 5 X1
- B225L Sideview Camera - Left video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 15 X1
- B225R Sideview Camera - Right video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 8 X1
- B225R Sideview Camera - Right video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 18 X1
- If 2 Ω or greater
Repair the open/high resistance in the circuit.
- If less than 2 Ω
- Engine running, transmission in R.
- Verify a clear surround vision image is displayed on the A11 Radio.
- If a clear surround vision image is not displayed
- Replace the appropriate camera.
- Engine running, transmission in R.
- Verify a clear surround vision image is displayed on the A11 Radio.
- If a clear surround vision image is not displayed, replace the K157 Video Processing Control Module.
- If a clear surround vision image is displayed, all OK.
- If a clear surround vision image is displayed
- All OK.
All camera images distorted with IO3
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K157 Video Processing Control Module. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 1 V between the signal circuit terminals listed below and ground:
- Camera signal (+) circuit terminal 6 X2
- Camera signal (-) circuit terminal 12 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:
- Camera signal (+) circuit terminal 6 X2
- Camera signal (-) circuit terminal 12 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 camera signal (+) circuit terminal 6 X2 and the A11 Radio video signal (+) circuit terminal 5 X1.
- 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 camera signal (-) circuit terminal 12 X2 and the A11 Radio video signal (-) circuit terminal 4 X1.
- 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 K157 Video Processing Control Module.
- Engine running, transmission in R.
- Verify a clear surround vision image is displayed on the A11 Radio.
- If a clear rear vision image is not displayed
Replace the A11 Radio.
- If a clear rear vision image is displayed
- If a clear rear vision image is not displayed
- All OK.
All camera images distorted with IO5 or IO6
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K157 Video Processing Control Module. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 1 V between the signal circuit terminals listed below and ground:
- Camera signal (+) circuit terminal 6 X2
- Camera signal (-) circuit terminal 12 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:
- Camera signal (+) circuit terminal 6 X2
- Camera signal (-) circuit terminal 12 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 camera signal (+) circuit terminal 6 X2 and the K74 Human Machine Interface Control Module video signal (+) circuit terminal 5 X2.
- 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 camera signal (-) circuit terminal 12 X2 and the K74 Human Machine Interface Control Module video signal (-) circuit terminal 6 X2.
- 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 K157 Video Processing Control Module.
- Engine running, transmission in R.
- Verify a clear surround vision image is displayed on the K74 Human Machine Interface Control Module.
- If a clear rear vision image is not displayed
Replace the A11 Radio.
- If a clear rear vision image is displayed
- If a clear rear vision image is not displayed
- All OK.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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