Motor Position Sensor
Reports the rotor's exact angle so the inverter can energise each motor phase at the right instant — to the electric motor what the crankshaft position sensor is to the engine, and losing it stops electric drive entirely rather than degrading it. On nearly every hybrid it is a resolver: a small transformer arrangement with no electronics, chosen because it survives the heat and oil inside a transaxle indefinitely. That toughness shapes the diagnosis — the sensor itself barely ever fails, while the wiring carrying its faint signals between transaxle and inverter fails routinely, so a resolver condemned before the harness has been tested is nearly always a misdiagnosis. On full hybrids the generator's resolver has a second consequence: the generator is what spins the engine to start it, so this sensor failing can present as an engine that will not start.
Also known as: resolver, rotor position sensor, motor angle sensor, mg1 resolver, mg2 resolver, motor speed sensor
Referenced by 59 codes
Codes involving this component (59)
- P0A3F Drive Motor A Position Sensor Circuit High
- P0A40 Drive Motor A Position Sensor Circuit Range/Performance High
- P0A41 Drive Motor A Position Sensor Circuit Low High
- P0A42 Drive Motor A Position Sensor Circuit High High
- P0A44 Drive Motor A Position Sensor Circuit Overspeed High
- P0A45 Drive Motor B Position Sensor Circuit High
- P0A46 Drive Motor B Position Sensor Circuit Range/Performance High
- P0A47 Drive Motor B Position Sensor Circuit Low High
- P0A48 Drive Motor B Position Sensor Circuit High High
- P0A4A Drive Motor B Position Sensor Circuit Overspeed High
- P0A4B Generator Position Sensor Circuit High
- P0A4C Generator Position Sensor Circuit Range/Performance High
- P0A4D Generator Position Sensor Circuit Low High
- P0A4E Generator Position Sensor Circuit High High
- P0A50 Generator Position Sensor Circuit Overspeed High
- P0C17 Drive Motor A Position Sensor Not Learned High
- P0C18 Drive Motor B Position Sensor Not Learned High
- P0C2F Internal Control Module Drive Motor/Generator - Engine Speed Sensor Performance High
- P0C4E Drive Motor A Position Exceeded Learning Limit High
- P0C4F Drive Motor B Position Exceeded Learning Limit High
- P0C50 Drive Motor A Position Sensor Circuit A High
- P0C51 Drive Motor A Position Sensor Circuit A Range/Performance High
- P0C52 Drive Motor A Position Sensor Circuit A Low High
- P0C53 Drive Motor A Position Sensor Circuit A High High
- P0C54 Drive Motor A Position Sensor Circuit A Intermittent/Erratic 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
- Hybrid Battery Contactor 136
- 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
- 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
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