U0198: Lost communication with the telematics control module
The vehicle network is not receiving messages from the telematics module, which handles emergency calls and connected services. The car drives fine.
| Code | U0198 |
|---|---|
| System | Communication network |
| Group | U01xx, Lost communication with control units |
| Type | Generic: it means the same on every make |
| Can you keep driving? | Yes, no rush |
What U0198 means
The telematics module has its own mobile connection and handles the automatic emergency call (eCall), connected services and the manufacturer’s app. This code means it has stopped talking to the other control units. The car drives the same, but those services, including the emergency call, may be unavailable.
Most common causes
- Low battery or recently disconnected
- Module’s internal backup battery worn out (many carry one for the emergency call)
- Blown fuse for the telematics module
- Loose or corroded connector on the module or its aerial
- Damaged network wiring
- Faulty telematics module
Symptoms
- Emergency call (SOS) warning light or message on
- The car’s app cannot connect to the vehicle
- Connected services or remote updates not working
- Sometimes no visible symptoms at all
Can you drive with U0198?
Yes, no rush You can drive normally, but the automatic emergency call may not work in a crash. Best not to leave it too long.
Open the bonnetthe in-depth explanation
How to check it
See whether the SOS light stays on after starting and whether the car’s app shows it online. If the message mentions the module’s backup battery, tell the garage exactly that, as it is a separate part.
How to read and clear U0198 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see U0198 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- U0193 The digital audio control unit A is not answering on the car network
- U0194 The digital audio control unit B is not answering on the car network
- U0196 The rear seat entertainment control unit is not answering on the car network
- U0197 The telephone control unit is not answering on the car network
- U0199 The door control unit A is not answering on the car network
- U019A The tachograph module is not answering on the car network
- U019B The battery charger control unit is not answering on the car network
- U019C The glow plug 2 control unit is not answering on the car network
- U0100 Lost communication with engine control module (ECM/PCM A)
- U0101 Lost communication with transmission control module (TCM)
- U0102 Lost communication with transfer case control module
- U0103 Lost communication with the gear shift module
What does code U0198 mean?
The telematics module has its own mobile connection and handles the automatic emergency call (eCall), connected services and the manufacturer’s app. This code means it has stopped talking to the other control units. The car drives the same, but those services, including the emergency call, may be unavailable.
Can you drive with U0198?
You can drive normally, but the automatic emergency call may not work in a crash. Best not to leave it too long.
How do you clear U0198?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, U0198 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
