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 K9 Body Control Module's ignition circuit terminal 23 X4. Use the connector end view to identify the ignition circuit terminal for each of those devices.
- Ignition OFF, disconnect the harness connectors at an easily accessible device that shares the K9 Body Control Module's ignition circuit terminal 23 X4. Ignition ON.
- Verify that the DTC U2099 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 K9 Body Control Module.
- Ignition OFF, disconnect the X4 harness connector at the K9 Body Control Module.
- Test for infinite resistance between the ignition circuit terminal 23 X4 at the K9 Body 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 K9 Body 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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