What it means
A control module has stopped receiving expected network messages from the windshield temperature sensor. The effect on vehicle functions depends on how the vehicle uses this sensor.
How it works
The windshield temperature sensor sends temperature information to vehicle modules over the communications network. U0658 sets when a module no longer receives the sensor's expected messages, leaving windshield temperature data unavailable to any functions that rely on it.
Common causes
Most likely first.
- Bus wiring open or shorted
- Module without power or ground
- Module failed
Symptoms
- Warning light or message related to the affected system
- Windshield temperature data may be unavailable
How to diagnose it
- Scan all modules and record freeze-frame data and related network faults to identify whether the loss is limited to the windshield temperature sensor.
- Check the vehicle display or climate system for missing or implausible windshield temperature data, if the scan tool exposes that value.
- Inspect the windshield temperature sensor connector and its harness for looseness, corrosion, water intrusion, or damage.
- Check the sensor module's fuses, power, and ground against the vehicle wiring information, since loss of supply can stop network communication.
- Test the sensor's network wiring for opens, shorts, and poor connections to the manufacturer's specification; if those checks pass, follow the vehicle's module diagnosis procedure.
Common fixes
- Reconnect a loose windshield temperature sensor connector.
- Clean or repair corroded terminals and damaged wiring in the sensor's network circuit.
- Restore the sensor module's power or ground after correcting the cause of the loss.
- Replace the windshield temperature sensor or its module only after tests show it is faulty.
Can I keep driving?
This fault usually affects only functions that use windshield temperature data, but those functions may not work as intended. Driving is generally possible if visibility and other vehicle systems are normal; address any warning or loss of defrost performance promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.