P1AF8
DTC P1AF8 or P1AFE
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 Descriptors
DTC P1AF8
- Drive Motor 1 Control Module Shutdown Performance
DTC P1AFE
- Drive Motor 2 Control Module Shutdown Performance
Circuit/System Description
The drive motor generator power inverter control module contains two motor control modules and the hybrid powertrain control module. Each motor control module operates its respective drive motor generator based upon hybrid powertrain control module commands. Each motor control module controls the speed, direction and output torque of its respective drive motor generator through the sequencing actuation of high current switching transistors called insulated gate bipolar transistors. Each drive motor generator operates utilizing 3 phase alternating current (AC) electricity. Each insulated gate bipolar transistors operate a single phase of the drive motor generator. Each phase is individually identified as U, V and W. Each motor control module monitors the current of each phase in order to detect drive motor generator power inverter control overcurrent conditions.
At ignition ON, each motor control module tests the integrity of the drive motor phase circuits by sequencing the insulated gate bipolar transistors between open and shorted states while simultaneously injecting a large amount of current into the phase circuits. The individual phase current sensors should all indicate similar current flow and the current flow should increase and decrease at known rates based upon the inductance of the drive motor.
Conditions for Running the DTC
* The ignition is ON.
* Ignition voltage is 8-18 V.
* High voltage has been enabled.
Conditions for Setting the DTC
The control module has detected a phase current that indicates an open or shorted condition exists in one or more of the 3 phase circuits.
Action Taken When the DTC Sets
* DTCs P1AF8 and P1AFE are Type A DTCs.
* The hybrid powertrain control module commands the battery energy control module to open the high voltage contactor relays.
Conditions for Clearing the DTC
DTCs P1AF8 and P1AFE are Type A DTCs.
Diagnostic Aids
* An intermittent loss of battery power to the drive motor generator power inverter control module may set this DTC.
* If the 3 phase cable terminal fasteners are not torque properly this DTC may set, and arc flash damage may occur. If any arc flash damage is present, replace all affected components.
Reference Information
Schematic Reference
Hybrid Controls Schematics Hybrid Controls Schematics
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
Verify that DTC P1AF0, or P1AF2 is not set.
If the DTC is set, refer to DTC P0AF7 P0AF7.
Circuit/System Testing
1. Verify that DTCs P0C01, P0C04, P0BFD, or P0BFE is not set.
• If the DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.
The High Voltage Disabling procedure will perform the following tasks:
* Identify how to disable high voltage.
* Identify how to test for the presence of high voltage.
* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
2. Perform the High Voltage Disabling High Voltage Disabling procedure for servicing at the drive motor generator control module cable connections.
3. Remove the 3-phase cable assembly from the T6 drive motor generator control module distribution box. Refer to Generator Control Module 3-Phase Cable Assembly Replacement Generator Control Module 3-Phase Cable Assembly Replacement.
4. Test for less than 0.5 ohm between each of the AC circuit terminals listed below:
* Drive motor 1st position phase U and phase V terminal
* Drive motor 1st position phase V and phase W terminal
* Drive motor 2nd position phase U and phase V terminal
* Drive motor 2nd position phase V and phase W terminal
• If not the specified value, test the AC circuit for an open/high resistance. If the circuit tests normal replace the appropriate M15 drive motor with generator assembly.
5. Test for infinite resistance between each of the AC circuit terminals listed below and ground:
* Drive motor 1st position phase U terminal
* Drive motor 1st position phase V terminal
* Drive motor 1st position phase W terminal
* Drive motor 2nd position phase U terminal
* Drive motor 2nd position phase V terminal
* Drive motor 2nd position phase W terminal
• If not the specified value, test the AC circuit for a short to ground or a short between the AC circuit terminals and the aluminum cable mounting block. If the circuit tests normal replace the appropriate M15 drive motor with generator assembly.
6. Replace the 3 phase cable assembly and the appropriate M15 drive motor with generator assembly. If the DTC resets replace the T6 drive motor power inverter module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Generator Control Module 3-Phase Cable Assembly Replacement Generator Control Module 3-Phase Cable Assembly Replacement
* Drive Motor with Generator Assembly Removal - 1st Position 8. Drive Motor with Generator Assembly Removal - 1st Position
* Drive Motor with Generator Assembly Removal - 2nd Position 13. Drive Motor with Generator Assembly Removal - 2nd Position
* Control Module References Control Module References for Drive Motor Generator Power Inverter Module replacement, setup, and programming