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.
DTC U1280 (Relay Control Module)
DTC U1280 : B-CAN Communication Bus Line Error (BUS-OFF)
NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
| DTC Description | DTC |
|---|---|
| U1280 B-CAN communication bus line error (BUS-OFF) |
DTC (Relay Control Module)
- Problem verification
-1. Clear the DTCs with the HDS.
-2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.
-3. Wait for at least 6 seconds.
-4. Check for DTCs with the HDS.
DTC Description DTC U1280 B-CAN communication bus line error (BUS-OFF) Is DTC U1280 indicated?
YES
Go to body control module DTC U1280 troubleshooting .
NO
Intermittent failure, the system is OK at this time. Check for loose or poor connections.
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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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