Hybrid Battery Contactor
The heavy relays that physically connect the traction battery to the car — one in each pole, closed when you press start, opened when you stop or crash. Both poles are switched deliberately so no single welded contact can leave the pack live, and the module verifies each one at every shutdown by opening it and watching whether voltage disappears — which is why stuck-closed codes are characteristically discovered at switch-off rather than felt on the road. The clunk from the back of a hybrid waking up is these closing. Their needs are modest but absolute: a contactor coil pulls in on twelve-volt power, so a tired twelve-volt battery produces contactor codes on a perfect pack — the cheapest cause and always the first check.
Also known as: main contactor, battery relay, hv contactor, high voltage relay, system main relay, smr, pack contactor
Referenced by 136 codes
Codes involving this component (136)
- P0AA0 Hybrid/EV Battery Positive Contactor Circuit High
- P0AA1 Hybrid/EV Battery Positive Contactor Circuit Stuck Closed High
- P0AA2 Hybrid/EV Battery Positive Contactor Circuit Stuck Open High
- P0AA3 Hybrid/EV Battery Negative Contactor Circuit High
- P0AA4 Hybrid/EV Battery Negative Contactor Circuit Stuck Closed High
- P0AA5 Hybrid/EV Battery Negative Contactor Circuit Stuck Open High
- P0AD9 Hybrid/EV Battery Positive Contactor Control Circuit/Open High
- P0ADD Hybrid/EV Battery Negative Contactor Control Circuit/Open High
- P0AE1 Hybrid/EV Battery Precharge Contactor Circuit High
- P0AE2 Hybrid/EV Battery Precharge Contactor Circuit Stuck Closed High
- P0AE3 Hybrid/EV Battery Precharge Contactor Circuit Stuck Open High
- P0AE4 Hybrid/EV Battery Precharge Contactor A Control Circuit/Open High
- P0B24 Hybrid/EV Battery A Voltage Unstable High
- P0B28 Hybrid/EV Battery B Voltage Unstable High
- P0B2C Hybrid/EV Battery C Voltage Unstable High
- P0B30 Hybrid/EV Battery D Voltage Unstable High
- P0C0B Drive Motor A Inverter Power Supply Circuit/Open High
- P0C0E Drive Motor B Inverter Power Supply Circuit/Open High
- P0C75 Hybrid/EV Battery System Discharge Time Too Short High
- P0C76 Hybrid/EV Battery System Discharge Time Too Long High
- P0C77 Hybrid/EV Battery System Precharge Time Too Short High
- P0C78 Hybrid/EV Battery System Precharge Time Too Long High
- P0C79 Drive Motor A Inverter Voltage Too High High
- P0C7A Drive Motor B Inverter Voltage Too High High
- P0C7B Generator Inverter Voltage Too High High
Other components in Hybrid Propulsion
- High Voltage Battery 795
- Power Inverter 370
- Motor Generator 249
- Hybrid/EV Battery Pack Sensor Module 243
- Battery Energy Control Module 228
- On-Board Charger 209
- Charge Port 131
- DC-DC Converter 99
- Inverter Coolant Pump 92
- Motor Current Sensor 73
- Electric A/C Compressor 63
- Inverter Coolant Temperature Sensor 60
- Motor Position Sensor 59
- Hybrid Battery Cooling Fan 54
- Battery Pack Coolant Control Valve 47
- Hybrid/EV Battery Pack Current Sensor 30
- Hybrid Powertrain Control Module 19
- Motor Temperature Sensor 18
- High Voltage Interlock Loop 15
- Drive Motor Control Module 15
- Active Engine Mount 6
- Starter/Generator 6
- High Voltage Service Disconnect 5
- Fuel Cell Stack 2
Information, not instruction
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