U11D1
Engine Speed Message Rationality
U11D1 is an OBD-II diagnostic trouble code meaning: Engine Speed Message Rationality. Common causes: malfunction of the crankshaft position sensor, problems with the can bus (break, short circuit). Estimated repair cost: $17–89.
Symptoms
- Incorrect tachometer readings
- Floating engine speed
- Check Engine Light Illuminates
- Problems with gear shifting (for automatic transmission)
- Loss of engine power
Causes
- Malfunction of the crankshaft position sensor
- Problems with the CAN bus (break, short circuit)
- Engine ECU malfunction
- Bad contacts in CAN bus connectors
- Software errors in car modules
How to Fix
- Check the condition of the crankshaft position sensor and its wiring
- Scan all modules for additional CAN bus errors
- Check the integrity of the CAN bus and the quality of connections
- Update ECU software (if available)
- Check the power supply and ground of the modules involved in data exchange
Related codes
FAQ
What does the U11D1 code mean?
U11D1 is an OBD-II diagnostic trouble code that indicates: Engine Speed Message Rationality
What causes a U11D1 error code?
The most common causes of U11D1 include: Malfunction of the crankshaft position sensor; Problems with the CAN bus (break, short circuit); Engine ECU malfunction; Bad contacts in CAN bus connectors.
How do I fix a U11D1 diagnostic trouble code?
To fix U11D1: Check the condition of the crankshaft position sensor and its wiring. Scan all modules for additional CAN bus errors. Check the integrity of the CAN bus and the quality of connections. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U11D1?
Limited driving only, diagnose soon
How much does it cost to fix U11D1?
The estimated repair cost for U11D1 is $17–89. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat