P0AAE
DTC P0AAD-P0AAF or P0AB2-P0AB4
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P0AAD
- Hybrid Battery Temperature Inlet Circuit Signal Performance
DTC P0AAE
- Hybrid Battery Temperature Inlet Circuit Signal Low Voltage
DTC P0AAF
- Hybrid Battery Temperature Inlet Circuit Signal High Voltage
DTC P0AB2
- Hybrid Battery Temperature Outlet Circuit Signal Performance
DTC P0AB3
- Hybrid Battery Temperature Outlet Circuit Signal Low Voltage
DTC P0AB4
- Hybrid Battery Temperature Outlet Circuit Signal High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The drive motor generator battery assembly has an air inlet and air outlet temperature sensors. The air inlet and air outlet temperature sensors are located on the inlet and outlet air ducts of the hybrid battery vent fan. The air temperature sensors are a variable resistor that measures the temperature of the inlet and outlet air. The control module supplies 5 volts to the signal circuit and a ground for the low reference circuit. The air inlet and outlet temperature sensor resistance changes with battery temperature. The lower the temperature, the higher the resistance of the sensor. The higher the temperature, the lower the resistance of the sensor. The battery energy control module (BECM) uses the air inlet and outlet temperature sensors to determine if air is circulating through the drive motor generator battery assembly.
Conditions for Running the DTC
* The vehicle power mode is RUN.
* Accessory voltage is 9-18 volts.
Conditions for Setting the DTC
* Circuit High - the hybrid battery air temperature is lower than -40°C (-40°F).
* Circuit Low - The hybrid battery air temperature is higher than 95°C (203°F).
* Circuit Performance inlet - The hybrid battery cooling fan is ON and inlet air temperature minus the air outlet temperature is greater than 10°C (50°F) for 9 out of 10 seconds.
* Circuit Performance outlet - The hybrid battery cooling fan is ON and outlet air temperature is greater than maximum battery temperature by 10°C (50°F) for 9 out of 10 seconds.
Action Taken When the DTC Sets
DTCs P0AAD, P0AAE, P0AAF, P0AB2, P0AB3, and P0AB4 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0AAD, P0AAE, P0AAF, P0AB2, P0AB3, and P0AB4 are Type B DTCs.
Diagnostic Aids
Wear insulated gloves while inspecting for the following conditions:
* Air inlet and outlet for blockage.
* Loose or poor connections at the BECM temperature sensor harness connector.
* Damage to the wire harness.
* Damage to the fan blades.
Special Tools
EL-48900 HEV Safety Kit
Circuit/System Verification
1. Ignition ON, with a scan tool, monitor the hybrid battery inlet and outlet temperature parameters. The hybrid battery inlet and outlet temperature should be between -40°C (-40°F) and 95°C (203°F).
2. Ignition ON, with a scan tool, command the hybrid cooling fan to 100 percent duty cycle. The inlet air temperature should decrease along with a corresponding decrease in the outlet temperature.
3. Operate the vehicle within the Conditions for Running the DTCs. You may also operate the vehicle within the conditions that you observed from the Freeze Fame/Failure Records data.
Circuit/System Testing
Danger: Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:
* Safety glasses with appropriate side shields when within 50 feet of the vehicle, either indoors or outdoors
* Certified and up-to-date Class "0" isolation gloves rated at 1000V with leather protectors
- Visually and functionally inspect the gloves before use.
- Wear the isolation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.
* Failure to follow the procedure exactly as written may result in serious injury or death.
Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling.
1. Remove the drive motor generator battery cover.
2. Verify that there is no cooling fan inlet duct or outlet duct obstruction.
3. Ignition ON, with a scan tool, verify the cooling fan is functional in all speed ranges.
4. Ignition OFF, disconnect the X3 connector at the BECM.
5. Test the resistance across each temperature sensor 5 volt reference and low reference circuits.
^ If greater than 25 ohms, replace the temperature sensor and sensor harness.
^ If less than 25 ohms, replace the BECM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair. Verification Tests
* Drive Motor Battery Control Module Harness Replacement
* Drive Motor Generator Battery Control Module and Bracket Replacement