U0101 on Chrysler: How to Diagnose & Fix
Lost Communication with TCM
1 Chrysler model · 1 documented issue · $200-$800 repair
U0101 on Chrysler by model: symptoms, diagnosis and fix
The ignition switch and SKREEM (Sentry Key Remote Entry Module) fail, preventing the vehicle from starting or causing intermittent no-start conditions. The SKREEM module reads the transponder in the key and communicates with the PCM. Failure causes 'no bus' communication errors.
Common Symptoms
- Vehicle cranks but won't start
- Security light flashing on dashboard
- Key won't turn in ignition
- Intermittent no-start that resolves after waiting
How to Fix
Replace ignition switch (Mopar 4685863AH) and/or SKREEM module (Mopar 56046149AE). New keys may need to be programmed at dealer. Try cleaning key and ignition cylinder first - cleaning the key transponder ring around the ignition cylinder resolves intermittent issues for some owners.
Sources for this issue (2)
U0101 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does U0101 mean on a Chrysler?
U0101 stands for "Lost Communication with TCM." This is a network communication code meaning a control module on the vehicle's data bus has lost communication with the Transmission Control Module (TCM). Modern vehicles use a shared data network (commonly CAN bus) so modules can exchange information; when the TCM stops responding or its messages disappear, other modules set this code. Because the transmission relies on this communication to shift properly, the vehicle may go into 'limp' mode, hold one gear, or refuse to shift normally. It generally indicates a wiring, power, ground, or connector problem on the network — or a failed TCM itself — rather than an internal mechanical transmission fault. On Chrysler it is documented across 1 model: Town & Country.
What are the most common causes of U0101?
The most common causes of U0101 are: Damaged, corroded, or loose TCM wiring or connectors, Open or short in the CAN bus data wiring, Blown fuse or lost power/ground to the TCM, Corrosion or water intrusion at the TCM connector, Faulty Transmission Control Module, Another faulty module dragging down the data bus, Poor ground connection in the network. The specific cause varies by vehicle.
How much does it cost to fix U0101 on a Chrysler?
Published repair estimates on Chrysler range from $200 to $800 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for U0101 on a different make?
View U0101 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.