Lost Communication with Telematic Control Module
The vehicle has lost the telematics module (eCall / Connected Services / TCU). Emergency call, remote services and over-the-air features are unavailable until the module is back online.
Affected components
- Telematics module
- Can bus wiring
Common causes
- High likelihood: TCU unpowered or backup battery dead
- Low likelihood: Mobile antenna disconnected
- Low likelihood: Gateway module routing CAN messages incorrectly
Possible symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.