Lost Communication with TPMS Module
The U0127 code indicates that the main control module (typically the BCM, PCM, or a dedicated TPMS receiver) has lost serial communication (CAN, LIN, or other proprietary bus) with the Tire Pressure Monitor (TPM) module. This happens when no status messages or pressure data are received from the sensors within a calibrated time, disabling the tire pressure monitoring function.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Faulty TPM (Tire Pressure Monitor) module
- Open circuit, short to ground, or short to battery on the communication bus (CAN High/Low or LIN line) to the TPM module
- Damaged, corroded, or loose connectors at the TPM module or receiver module
- Loss of power (B+) or ground to the TPM module
- Internal failure of the receiving control module (BCM/PCM) that manages communication
- Electromagnetic interference (EMI) or a collapsed data bus caused by another module
3. Symptoms You Will Notice
- TPMS warning light illuminated on the dashboard
- Tire pressure readings not displayed or showing dashes
- Possible loss of other vehicle functions if the bus is shared
4. Step-by-Step Diagnosis
Scan for all stored codes and note any related communication codes
Inspect the TPM module connectors for corrosion, damage, or loose terminals
Check for proper power and ground at the TPM module
Test the communication bus (CAN/LIN) for shorts, opens, or excessive resistance
If wiring is intact, attempt to communicate with the TPM module using a scan tool; if no response, suspect a faulty module
Check for aftermarket accessories that may cause EMI or bus interference
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the vehicle is generally safe to drive, but you will lose tire pressure monitoring. Check tire pressures manually and drive cautiously until repaired.
How much does it cost to fix?▼
Diagnosis typically costs $100-$150. Repair costs vary: a new TPM sensor module can be $50-$200 plus labor, while wiring repairs may be $100-$300. Total cost usually ranges from $150 to $500.