Network
generic / SAE
U0634
Lost Communication With Hybrid/EV Battery Pack Coolant Temperature Sensor A
The vehicle bus reports loss of communication with smart HV battery pack coolant temperature sensor A. Battery cooling and charge/discharge limits switch to a substitute value.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number6 / 34
Possible causes
- Bus wiring open or shorted high
- Module without power or ground medium
- Module failed medium
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
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 120–1200 €
- Estimated time: 0.5–3 h
- Component: hv battery coolant temp sensor a
- Component: vehicle bus wiring
- MIL / check engine light
- drive cycle required
- limp mode possible
Sources
References
sae:J2012