Network, generic

U0198 Lost Communication With Telematic Control Module

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U0198 marks the telematic control module as silent; that unit holds the cellular modem for remote apps, emergency and assistance calls. Ford's APIM stores it on 2012-2018 Focus Electric, Fusion Energi and C-MAX Energi when the TCU hangs: SSM 46534 and 47198 report a drained battery, dead MyFord Mobile features and no modem ESN, cured by pulling the TCU fuse for five minutes and reprogramming. For the 2023 Super Duty, SSM 51578 treats U0198:87 in the BCM after a self-test as a false history entry to ignore if the MIL is off. Mazda SA-029/20 (Mazda3, CX-30) ties U0198:00 in the BCM to the emergency call unit; GM PIT5422 (Equinox, Terrain) traces it to water in connector X901. U0197 is the phone module, U0499 invalid data.

Likely causes

Telematics unit hung or outdated software (Ford TCU reprogramming)
Water or corrosion in a body harness connector (GM X901)
Low-speed bus wire pinched or chafed in the roof or body
False history entry from a module self-test (Ford Super Duty)
Telematic control module faulty

Symptoms

  • Remote app, emergency or assistance call unavailable
  • Battery drained overnight (Ford plug-in models)
  • Network warning in the cluster, often with further U-codes

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–800
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

telematics modulecan bus wiring

Related codes

U0140U0155U0197U0499

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.