Network & communication
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Lights the check engine lamp
U0635: Lost Communication With Hybrid/EV Battery Pack Coolant Temperature Sensor B
Standardized SAE J2012 code · U06xx codes
What does U0635 mean?
The vehicle bus reports loss of communication with smart HV battery pack coolant temperature sensor B. Battery cooling and charge/discharge limits switch to a substitute value.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Common causes
- High Bus wiring open or shorted
- Medium Module without power or ground
- Medium Module failed
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of U0635 on the same make and model first.
U0635 in the community
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