U0101: Lost Communication with TCM
5 vehicles · 5 makes · $200-$8,000 repair
U0101 is an OBD-II diagnostic trouble code meaning “Lost Communication with TCM.” Communication lost with the transmission control module. Transmission may default to limp mode. This code appears across 5 vehicle models from 5 manufacturers, with repair costs ranging from $200 to $8,000.
Common Causes
Typical Repair Cost
Based on 5 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose U0101, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (5)
FAQ
What does U0101 mean?
U0101 stands for "Lost Communication with TCM." Communication lost with the transmission control module. Transmission may default to limp mode.
What are the most common causes of U0101?
The most common causes of U0101 are: TCM failure, CAN bus wiring issue, TCM power/ground fault, Corroded connector, After battery disconnect. The specific cause varies by vehicle.
How much does it cost to fix U0101?
Repair costs for U0101 range from $200 to $8,000, depending on the vehicle and root cause.
Which vehicles are affected by U0101?
Au7o has documented U0101 across 5 vehicle models from 5 manufacturers: Audi, Chevrolet, Chrysler, Dodge, GMC.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.