OBD-II code · Network

U0198 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.

Is it safe to drive with U0198?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyTCU unpowered or backup battery dead
  • Less likelyMobile antenna disconnected
  • Less likelyGateway module routing CAN messages incorrectly

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

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
0.5–3 h
Emissions test
Usually unaffected
Parts involved
Telematics Module, Can Bus Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.