When it comes to diagnosing Ford vehicles with the U0198 code, things can get a bit tricky. The U0198 code is a lost communication, or communication error, between the vehicle’s telematic control module (TCM) and the telematics control unit (TCU). The TCM continuously monitors the controller area network (CAN) for messages from the TCU, and when the TCM does not receive the TCU message within the specified amount of time, the U0198 code is triggered. Diagnosing the issue requires a thorough investigation of all other Service Bulletin Diagnostic Trouble Codes (SOBDMC) and SOBDMC related symptoms. To help with this process, there are a number of Ford Service Bulletins available, ranging from 13-9-19 to SSM51298.
Causes and Solutions of Ford U0198 Code
| Cause | Solution |
|---|---|
| Communication Error | Check for other SOBDMC DTCs or SOBDMC related symptoms. |
| Incorrect CAN Message | Perform a CAN bus diagnostic to determine if the CAN message is correct. |
| TCM Software Issue | Update the TCM software to the latest version. |
| Faulty TCM | Replace the TCM with a new one. |
Communication Error
When diagnosing Ford vehicles with the U0198 code, one of the primary causes is a communication error between the TCM and TCU. To determine if this is the culprit, it’s important to check for other Service Bulletin Diagnostic Trouble Codes (SOBDMC) or SOBDMC related symptoms. If these are present, then the communication error may be the cause of the U0198 code.
Incorrect CAN Message
Another cause of the U0198 code is an incorrect controller area network (CAN) message. The TCM continuously monitors the CAN for messages from the TCU and if the message is incorrect or malformed, the U0198 code will be triggered. To determine if this is the cause of the code, a CAN bus diagnostic should be performed.
TCM Software Issue
If the TCM is not receiving the correct messages, it may be due to a software issue. In this case, updating the TCM software to the latest version should resolve the issue. Ford has provided a number of Service Bulletins for this purpose, ranging from 13-9-19 to SSM51298.
Faulty TCM
If the TCM software has been updated but the U0198 code still persists, then the TCM may be faulty and need to be replaced. In this case, a new TCM should be installed to resolve the code.
Conclusion
The Ford U0198 code is a lost communication, or communication error, between the vehicle’s telematic control module (TCM) and the telematics control unit (TCU). Causes of the code can range from a communication error to an incorrect CAN message to a software issue or a faulty TCM. Diagnosing the issue requires a thorough investigation of all other Service Bulletin Diagnostic Trouble Codes (SOBDMC) and SOBDMC related symptoms. With the right knowledge and tools, the Ford U0198 code can be easily diagnosed and resolved.
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