P0A2D
DTC P0A2B-P0A2D or P0A31-P0A33
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0A2B
- Drive Motor 1 Temperature Sensor Performance
DTC P0A2C
- Drive Motor 1 Temperature Sensor Circuit Low Voltage
DTC P0A2D
- Drive Motor 1 Temperature Sensor Circuit High Voltage
DTC P0A31
- Drive Motor 2 Temperature Sensor Performance
DTC P0A32
- Drive Motor 2 Temperature Sensor Circuit Low Voltage
DTC P0A33
- Drive Motor 2 Temperature Sensor Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The motor temperature sensor (MTS) is a non-serviceable part of the drive motor generator stator assembly. The MTS sensor is a thermistor, or a resistor that changes value when the temperature changes. The sensor has a negative-temperature coefficient. This means that as the temperature increases, the resistance decreases, and as the temperature decreases, the resistance increases. The motor control module (MCM) supplies about a 5-volt reference signal to the sensor and measures the voltage drop in the circuit. When the motor is cold, the sensor resistance is high and the MCM detects high signal voltage. As the motor temperature increases, the resistance of the sensor decreases, which lowers the signal voltage.
Conditions for Running the DTC
P0A2B and P0A31
* DTCs P0A2C, P0A2D, P0AEF, P0AF0, P0BD3, P0BD4, P0BDD, P0BDE are not set.
* Ignition ON after the engine has been OFF for at least 6 hours.
* Average of phase U, V, W inverter temperatures is greater than -12°C (+10°F).
* Motor temperature is greater than -40°C (-40°F).
P0A2C, P0A2D, P0A32 and P0A33
The ignition is ON.
Conditions for Setting the DTC
P0A2B and P0A31
The average of the three motor phase sensor temperatures and the motor temperature are not within 28°C (50°F) of each other at ignition ON for 11 seconds.
P0A2C and P0A32
Motor temperature sensor signal is less than 0.29V for 11 seconds.
P0A2D and P0A33
Motor temperature sensor signal is greater than 4.42V.
If this condition is observed at Ignition ON, the drive motor generator must operate at greater than 20 Nm (14.75 lb ft) of torque for a cumulative time of 1.5 minutes before the DTC will set.
If this condition is observed after Ignition ON, the DTC will set within 11 seconds when the above condition is met.
Action Taken When the DTC Sets
* DTCs P0A2B-P0A2D, P0A31-P0A33 are Type B DTCs.
* The HPCM commands the SERVICE HYBRID SYSTEM message to display on the instrument panel.
Conditions for Clearing the DTC
DTCs P0A2B-P0A2D, P0A31-P0A33 are Type B DTCs.
Diagnostic Aids
* The motor temperature sensor can be damaged by excessive electric current. Test the sensor for an open condition whenever a short to voltage condition is observed.
* Test the X176 transmission 20-way connector for proper terminal contact whenever an open or high resistance circuit condition is observed.
* The HPCM motor temperature scan tool parameter display will default to 120°C (248°F) whenever an open or shorted signal circuit is observed.
Reference Information
Schematic Reference
Hybrid Controls Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Drive Motor Generator Control Module Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
J 44152 - Jumper Harness (20-Pins)
Circuit/System Verification
P0A2B and P0A31
1. Allow the vehicle to cool to ambient temperature by leaving the ignition OFF for 6 or more hours.
2. Ignition ON, observe HPCM Motor 1 temperature, Motor 2 temperature, and phase U, V, W inverter temperature scan tool parameters.
• The Motor 1 Temperature, Motor 2 Temperature, and phase U, V, W inverter temperature parameters should be within 28°C (50°F) of each other and ambient temperature.
P0A2C, P0A2D, P0A32, and P0A33
Ignition ON, observe the MCM motor temperature scan tool parameter.
The motor temperature parameter should be between 0.29V and 4.42V.
Circuit/System Testing
1. Ignition OFF, disconnect the transmission X176 20-way harness connector.
Note: The ignition must be ON to test the low reference circuit. Other DTCs will set with the X176 connector disconnected.
2. Ignition ON, test the vehicle harness side for less than 8 ohms between the low reference circuit terminal and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PIM.
3. Ignition ON, verify the scan tool motor temperature sensor parameter is greater than 4.42V.
• If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the PIM.
4. Install a 3-amp fused jumper wire between the signal circuit terminal and the low reference circuit terminal. Verify the scan tool motor temperature sensor parameter is less than 0.29V.
Note: If a short to voltage is found, test the motor temperature sensor for damage.
• If greater than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PIM.
5. Connect the J 44152 - jumper harness to the X176 transmission 20-way connector at the transmission. Measure and record the resistance between the sensor signal and low reference terminals. Compare the actual sensor and circuit resistance to the expected sensor resistance. Refer to Temperature Versus Resistance (Electrical Specifications).
• If the resistance is near the expected value, test the transmission internal harness signal circuit for a short to ground. If the circuit tests normal, replace the drive motor generator stator assembly.
• If the resistance is not near the expected value, test the transmission internal harness signal and low reference circuits for an open or shorted together condition. If the circuits test normal, replace the drive motor generator stator assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control Module References (Programming and Relearning) for PIM replacement, setup, and programming
* Automatic Transmission Wiring Harness and Output Speed Sensor Removal (Overhaul)
* Drive Motor Generator Rotor and Stator Removal - Unit A (Overhaul)
* Drive Motor Generator Rotor and Stator Removal - Unit B (Overhaul)