Lost Communication with TCM
The MAXXFORCE-U0101 (MaxxForce) diesel fault code means: Lost Communication with TCM. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- advanced
- Estimated cost
- $250-$2,800
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Common Symptoms
- Transmission limp
- No shift
- CEL
Probable Causes (Ranked by Likelihood)
- Allison / Eaton TCM failure Likely
- CAN fault Possible
Step-by-Step Diagnostic Procedure
Check for power at TCM.
Test CAN continuity to TCM.
Frequently Asked Questions
What is U0101 on a MaxxForce 13 (12.4L)?
U0101 on a MaxxForce 13 (12.4L) (2008-2014) indicates: Lost Communication with TCM. This is a known fault code on the MaxxForce engine family and typically points to the causes listed above.
Can I drive with U0101 on my MaxxForce?
Only drive short distances to reach a repair facility. Continued operation may cause further damage or progressive derate.
How much does it cost to fix MaxxForce U0101?
Repair cost is typically $250-$2,800 depending on the underlying cause and shop rate. Many MaxxForce faults (especially EGR cooler, head bolt, and VGT repairs) are major expenses that drove fleet owners to repower with Cummins or retire these trucks early.
U0101 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: