U0101
Lost Communication With TCM
U0101 is an OBD-II diagnostic trouble code meaning: Lost Communication With TCM. Common causes: open or short circuit in the communication circuit between the ecm and tcm, poor contact in module connectors. Estimated repair cost: $56–278.
Symptoms
- Check Engine light comes on
- The car goes into emergency mode
- Gear shifting problems
- Reduced engine power
- Possible jerking when moving
Causes
- Open or short circuit in the communication circuit between the ECM and TCM
- Poor contact in module connectors
- TCM module malfunction
- TCM power problems
- Wiring harness damage
How to Fix
- Check continuity of wires between ECM and TCM
- Inspect and clean the contacts in the connectors
- Check TCM power and ground
- Scan modules for other errors
- Replace TCM if necessary
Related codes
Error U0101 by Vehicle Brand
FAQ
What does the U0101 code mean?
U0101 is an OBD-II diagnostic trouble code that indicates: Lost Communication With TCM
What causes a U0101 error code?
The most common causes of U0101 include: Open or short circuit in the communication circuit between the ECM and TCM; Poor contact in module connectors; TCM module malfunction; TCM power problems.
How do I fix a U0101 diagnostic trouble code?
To fix U0101: Check continuity of wires between ECM and TCM. Inspect and clean the contacts in the connectors. Check TCM power and ground. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U0101?
Yes, but get it checked soon
How much does it cost to fix U0101?
The estimated repair cost for U0101 is $56–278. Actual cost depends on your vehicle, location, and labor rates.
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