P2BC7 code meaning
Battery Charging System Positive Contactor B Control Circuit/Open
What P2BC7 means
P2BC7 concerns the coil drive line of positive charging contactor B, not its main contacts: the module compares its command with the voltage and current it measures on that line and sets the code when the line is broken or the driver that does not follow. No manufacturer documents P2BC7 publicly. GM's test for the twin code of contactor A (P0D0A) on the Chevrolet Volt shows the method: with the driver off, more than 4 V on the output means an open, and with it on, a coil current under 57 mA counts as open too; the code needs 40 bad readings in a window of 50, taken every 12.5 ms. Monitoring of charging hardware on plug-in models is a CARB requirement. Usual causes: broken wire, loose plug, open coil. Range/performance, low and high are P2BC8–P2BCA, the minus side P2BCE. The charging mode behind contactor B is lost.
P2BC7 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2BC7
- Charging via the contactor B path not possible
- Charging fault indication
Common causes of P2BC7
- Most likelyControl wire or connector to contactor B interrupted
- PossibleCoil of positive contactor B open
- Less likelyDriver stage in the control module defective
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Bcs pos contactor bWiring harnessBms
What each part of P2BC7 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| B | Area: hybrid propulsion. |
| C7 | The exact fault in that area. |
What to do next
- Note P2BC7 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 P2BC7
What does P2BC7 mean?
P2BC7 means "Battery Charging System Positive Contactor B Control Circuit/Open". P2BC7 concerns the coil drive line of positive charging contactor B, not its main contacts: the module compares its command with the voltage and current it measures on that line and sets the code when the line is broken or the driver that does not follow. It is a generic code, so it means the same on every make.
Is it safe to drive with P2BC7?
P2BC7 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P2BC7 fail an emissions test?
P2BC7 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P2BC7 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P2BC7 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.