P0ADC code meaning
Hybrid/EV Battery Positive Contactor Control Circuit High
Powertrain system Generic code P0Axx codes Check engine light
What P0ADC means
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.
P0ADC at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0ADC
- Hybrid or EV warning light
- High-voltage system disabled, vehicle not ready
- Possible related stuck-closed codes
Common causes of P0ADC
- Most likelyCoil control wire shorted to 12 V
- PossibleDamaged harness or connector at the battery disconnect unit
- Less likelyDriver stage in the battery controller shorted
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery pos contactorWiring harnessBms
What each part of P0ADC means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| DC | The exact fault in that area. |
What to do next
- Note P0ADC and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0ADC
What does P0ADC mean?
P0ADC means "Hybrid/EV Battery Positive Contactor Control Circuit High". P0ADC indicates that the positive contactor drive circuit carries too much voltage for the commanded state, usually a short to battery voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P0ADC?
Drive gently and only to a workshop. With P0ADC the car can go into limp mode (reduced power) to protect itself.
Will P0ADC fail an emissions test?
Yes, it can. P0ADC is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0ADC to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0ADC clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.