What it means
Fault on the ignition OFF input — module does not detect OFF state correctly. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
At a glance
- Usually lights the warning light of the system that lost communication
How it works
The ignition OFF input tells the control module when the vehicle's ignition switch is off. The module sets U3011 when it fails to recognize that OFF state correctly, which can disrupt its communication with other modules.
Common causes
Most likely first.
- Ignition switch contacts worn
- Gateway module routing CAN messages incorrectly
- CAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Scan all modules for communication codes and record freeze-frame data to see which modules stopped responding and when.
- Check live data for the module's ignition state while switching the ignition between ON and OFF.
- Inspect the ignition switch connector and related wiring for loose terminals, wear, corrosion, or damage.
- Test the ignition OFF input circuit from the switch to the module for continuity and unwanted resistance.
- If the input changes correctly at the module, check gateway routing and CAN network termination against the manufacturer's specification.
Common fixes
- Repair a loose, damaged, or corroded ignition switch connection.
- Replace a worn ignition switch if its OFF signal is incorrect.
- Repair damaged wiring in the ignition OFF input circuit.
- Correct a gateway routing fault or CAN termination fault if testing confirms it.
Can I keep driving?
If the engine runs normally and no critical functions are affected, a short drive may be possible, but multiple warnings or loss of dependent functions can make the vehicle unpredictable. Avoid driving if steering, braking, powertrain, or other safety-related functions are impaired.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.