P1791moderate severityPowertrain
Transmission System Voltage Reference
on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD
What this code means
The transmission control system detected an incorrect reference voltage. This can affect solenoid and sensor operation.
Symptoms
- Erratic shifting
- Transmission warning light
- Default limp mode
Common causes
- Poor ground or power connection
- Wiring fault in reference circuit
- Faulty TCM
- Charging system fault
Diagnostic steps
- Check system and reference voltages
- Inspect grounds and power feeds
- Test reference circuit wiring
- Repair wiring or replace TCM
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