P1633high severityPowertrain
Ignition Supply Power Circuit Low Voltage
on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD
What this code means
The PCM detected low voltage on its ignition supply power circuit. The ignition power circuit provides run/start voltage to the PCM.
Symptoms
- Check Engine Light
- Engine stalling
- Poor performance
- Intermittent no-start
- Multiple erratic codes
Common causes
- Faulty ignition switch
- Loose ignition power connection
- Blown fuse
- Damaged wiring
- Corroded ignition switch connector
Diagnostic steps
- Test voltage at PCM ignition power circuit
- Check ignition switch output
- Inspect ignition power fuse
- Test wiring for resistance
- Check connector at ignition switch
Repair notes
Check ignition switch, fuse, and wiring. Replace ignition switch if voltage output is low.
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