U0198
Lost Communication With Telematic Control Module
Communication / telematics
Generic OBD-II
Low
What it means
U0198 sets when a module loses communication with the telematics control module — the unit behind connected services like emergency calling, remote start/unlock, and vehicle tracking. The car drives normally, but those connected and safety-call features may not work until it's restored. On some vehicles automatic crash notification depends on this module.
Low
Can I keep driving? Yes — only connected services (emergency calling, remote features, tracking) are affected; the vehicle drives normally.
Common symptoms
What you'll notice
- Connected services (remote start/unlock, app features) not working
- Emergency/SOS calling unavailable
- Telematics module unreachable by a scan tool
- Warning or message about connected services
Common causes
Most likely first
- Loss of power or ground to the telematics moduleLikely
- Damaged wiring or connector at the moduleCommon
- Bus fault between the telematics module and the networkCommon
- Antenna or subscription/activation issue (varies by system)Less often
- Failed telematics control moduleLess often
How to diagnose & fix
Work through it in order
- Scan all modules and confirm the telematics unit is offline.
- Check the module's power, ground, and connector.
- Inspect the bus wiring between the telematics module and the network.
- Verify the module's software and activation status where applicable.
- Repair the wiring or replace and program the telematics module, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with U0198?+
Yes for normal driving. Note that emergency auto-call features may be down, so don't count on them until it's fixed.
Can I just clear U0198?+
You can, but it returns while the module is offline; the wiring or module fault has to be addressed.
Related codes
Often seen with U0198
Read & clear U0198 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX