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
Use the schematic to determine which devices are on the K124 active safety control module's ignition circuit 9 X1. Use the connector end view to identify the object detection ignition circuit terminal for each of those devices.
- Ignition OFF, disconnect the harness connectors at an easily accessible device that shares the K124 active safety control module's ignition circuit 9 X1. Ignition ON.
- Verify that the DTC U209E remains current.
- If the DTC becomes history
Replace the device that was just disconnected.
- If the DTC remains current
- If the DTC becomes history
- With the prior devices disconnected, repeat steps 1 and 2 for each device on the ignition circuit except the K124 active safety control module.
- Ignition OFF, disconnect the X1 harness connector at the K124 active safety control module.
- Test for infinite resistance between the ignition circuit terminal 9 X1 at the K124 active safety control module and ground.
- If less than infinite resistance
Repair the short to ground on the circuit.
- If infinite resistance
- If less than infinite resistance
- Replace the K124 active safety control module.
Use the Manual With the Right Hardware
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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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