P0ADCHybrid/EV Battery Positive Contactor Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0ADC indicates that the positive contactor drive circuit carries too much voltage for the commanded state, usually a short to battery voltage. In GM's 2016-19 hybrid tables the driver output, with the contactor commanded off, reads between 5.27 and 19.7 V for 40 of 50 samples at 12.5 ms, Type B with two trips. The 2013 eAssist controller sets it for a short to power on the low-side driver in the on state, 3 of 5 samples. CARB requires such circuit monitoring for hybrid components. Siblings are P0AD9 (open) and P0ADB (low). A short to power can energize the coil unintentionally, so the contactor may not open when it should.
- What you may notice
- Hybrid or EV warning light
- High-voltage system disabled, vehicle not ready
- Possible related stuck-closed codes
- Likely causes
- LikelyCoil control wire shorted to 12 V
- PossibleDamaged harness or connector at the battery disconnect unit
- RareDriver stage in the battery controller shorted
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.