P0A2B
DTC P0A2B-P0A2D or P0A31-P0A33
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions 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 is a non-serviceable part of the drive motor generator assembly. The motor temperature 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 supplies a 5 V 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 motor control module 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 3 seconds.
P0A2C and P0A32
Motor temperature sensor signal is less than 0.29 V for 3 seconds.
P0A2D and P0A33
Motor temperature sensor signal is greater than 4.42 V when drive motor generator torque is greater than 20 Nm (14.75 lb ft) for 3 seconds.
Action Taken When the DTC Sets
* DTCs P0A2B-P0A2D, P0A31-P0A33 are Type B DTCs.
* The hybrid powertrain control module requests the SERVICE HYBRID SYSTEM message to display on the drive information center.
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 24-way connector for proper terminal contact whenever an open or high resistance circuit condition is observed.
* The hybrid powertrain control module motor temperature scan tool parameter display will default to 120°C (248°F) when an open or shorted signal circuit is detected.
Reference Information
Schematic Reference
Hybrid Controls Schematics Hybrid Controls Schematics
Connector End View Reference
Component Connector End Views Connector Views
Description and Operation
Drive Motor Generator Control Module Description and Operation Drive Motor Generator Control Module Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
DT-48493 - Jumper Harness, 24 terminal
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
P0A2B and P0A31
1. Allow the vehicle to cool to ambient temperature by leaving the ignition OFF for at least 6 hours.
2. Ignition ON, observe 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 motor control modules motor temperature scan tool parameter.
The motor temperature parameter should be between 0.29 V and 4.42 V.
Circuit/System Testing
1. Ignition OFF, disconnect the transmission X176 24-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. Connect DT-48493 - jumper harness.
3. Ignition ON, test the jumper harness side for less than 8 ohms between the low reference circuit terminals listed below and ground for the appropriate drive motor generator:
* Drive motor 1 low reference circuit terminal 19
* Drive motor 2 low reference circuit terminal 23
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the T6 drive motor generator power inverter module.
4. Ignition ON, verify the scan tool motor temperature sensor parameter is greater than 4.42 V.
• If less than the specified value, test the motor temperature sensor signal circuit for a short to ground. If the circuit tests normal, replace the T6 drive motor generator power inverter module.
5. Install a 3-amp fused jumper wire between the signal circuit terminal and the low reference circuit terminal listed below for the appropriate drive motor generator. Verify the scan tool motor temperature sensor parameter is less than 0.29 V:
* Drive motor 1 terminals 13 and 19
* Drive motor 2 terminals 22 and 23
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 T6 drive motor generator power inverter module.
6. Ignition OFF, connect the DT-48493 - jumper harness to the X176 transmission 24-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 [1][2]Power Control System, Hybrid Drive.
• 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 M15 drive motor generator.
• 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 M15 drive motor generator.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Control Module References Control Module References for Drive Motor Generator Power Inverter Module replacement, setup, and programming
* Transmission Control Wiring Harness Extension Harness Removal 5. Transmission Control Wiring Harness Extension Harness Removal
* Drive Motor with Generator Assembly Removal - 1st Position 8. Drive Motor with Generator Assembly Removal - 1st Position
for Drive Motor with Generator Assembly replacement
* Drive Motor with Generator Assembly Removal - 2nd Position 13. Drive Motor with Generator Assembly Removal - 2nd Position
for Drive Motor with Generator Assembly replacement