What it means
The positive contactor C of the battery charging system reports a stuck closed condition. HV charging path cannot be commanded reliably.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Positive contactor C is a high-voltage switch in the battery charging path. The control module checks whether it opens when commanded; this code sets when the contactor is still conducting or its feedback indicates closed after an open command.
Common causes
Most likely first.
- Contactor contacts welded closed
- Output driver stuck on
- Carbon or debris buildup preventing free movement
Symptoms
- Hybrid or EV system warning
- Charging may be disabled
- Vehicle may not start or enter Ready mode
How to diagnose it
- Read freeze-frame data and related hybrid or EV codes to see when positive contactor C was commanded open and what feedback the module recorded.
- Check the vehicle's warning messages and charging or Ready status to confirm whether the fault coincides with a failed charging attempt or start-up.
- With the vehicle powered down according to the manufacturer's safety procedure, have a qualified technician inspect the positive contactor C connector and accessible wiring for damage, corrosion, or signs of overheating.
- Use the scan tool's contactor command and feedback data, if available, to compare the commanded state of positive contactor C with its reported state.
- Have a qualified technician test whether positive contactor C still conducts when commanded open and distinguish welded contacts from a driver or feedback fault using the manufacturer's procedure.
Common fixes
- Repair a loose, damaged, or corroded positive contactor C connector or low-voltage control wire.
- Repair the contactor driver circuit if testing shows its output is stuck on.
- Replace positive contactor C if its contacts are welded or it cannot open as commanded.
Can I keep driving?
Charging may be disabled, and the vehicle may fail to enter Ready mode or start. Avoid relying on the vehicle until the fault is diagnosed; high-voltage contactor work should be handled by a qualified technician.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.