Cause
Faulty battery contactor
One of the heavy relays that connect the traction battery failing at its job — a coil that no longer pulls in, contacts worn or burnt until they carry current badly, or a mechanism gone lazy with age. The welded variant has its own entry; this one covers everything short of it.
The contactor is the last suspect on its own codes, not the first. A contactor needs a healthy twelve-volt supply to close, an intact command wire to be told to, and a working feedback circuit to be believed — and all three fail more often than the relay itself. The stuck-open presentation (a car that will not wake) starts at the twelve-volt battery and the service plug; the contactor earns its place at the end of that list, partly because replacing it means opening the battery pack, which is qualified-workshop territory with a bill to match.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
1 of the 47 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (47)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0AE1 Hybrid/EV Battery Precharge Contactor Circuit Likely for this code High
- P0C0B Drive Motor A Inverter Power Supply Circuit/Open Likely for this code High
- P0C0C Drive Motor A Inverter Power Supply Circuit Low Likely for this code Moderate
- P0C0E Drive Motor B Inverter Power Supply Circuit/Open Likely for this code High
- P0C0F Drive Motor B Inverter Power Supply Circuit Low Likely for this code Moderate
- P0C79 Drive Motor A Inverter Voltage Too High Likely for this code High
- P0C7A Drive Motor B Inverter Voltage Too High Likely for this code High
- P0C7B Generator Inverter Voltage Too High Likely for this code High
- P0D07 Battery Charging System Positive Contactor A Circuit Likely for this code High
- P0D09 Battery Charging System Positive Contactor A Stuck Open Likely for this code High
- P0D0A Battery Charging System Positive Contactor A Control Circuit/Open Likely for this code Moderate
- P0D0B Battery Charging System Positive Contactor A Control Circuit Range/Performance Likely for this code Moderate
- P0D0C Battery Charging System Positive Contactor A Control Circuit Low Likely for this code Moderate
- P0D0D Battery Charging System Positive Contactor A Control Circuit High Likely for this code Moderate
- P0D0E Battery Charging System Negative Contactor A Circuit Likely for this code High
- P0D10 Battery Charging System Negative Contactor A Stuck Open Likely for this code High
- P0D11 Battery Charging System Negative Contactor A Control Circuit/Open Likely for this code Moderate
- P0D12 Battery Charging System Negative Contactor A Control Circuit Range/Performance Likely for this code Moderate
- P0D13 Battery Charging System Negative Contactor A Control Circuit Low Likely for this code Moderate
- P0D14 Battery Charging System Negative Contactor A Control Circuit High Likely for this code Moderate
- P0D25 Battery Charger System Precharge Time Too Short Likely for this code High
- P0E56 DC/DC Converter Input Voltage Too Low Likely for this code High
- P0E6A Battery Charging System Precharge Contactor Circuit Likely for this code High
- P0E6B Battery Charging System Precharge Contactor Circuit Stuck Closed Likely for this code High
- P0E6C Battery Charging System Precharge Contactor Circuit Stuck Open Likely for this code High
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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