• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|
Temperature Sensors 1-4 5 volt Reference | P0A9D, P0AC7, P0ACC, P0AEA | P0A9E, P0AC8, P0ACD, P0AEB | P0A9E, P0AC8, P0ACD, P0AEB |
Temperature Sensors 1-4 Low Reference | -- | P0A9E, P0AC8, P0ACD, P0AEB | -- |
Circuit | Short to Ground | Open | Short to Voltage |
---|---|---|---|
Operating Conditions: Accessory voltage is 9-18 volts, vehicle power mode is RUN Parameter Normal Range: 26°C (79°F) | |||
Hybrid Batt Mod 1-4 Temperature 5 volt Reference | 100°C (212°F) | -40°C (-40°F) | -40°C (-40°F) |
Circuit | Short to Ground | Open | Short to Voltage |
---|---|---|---|
Operating Conditions: Accessory voltage is 9-18 volts, vehicle power mode is RUN Parameter Normal Range: 3.2 volts | |||
Hybrid Batt Mod 1-4 Temperature 5 volt Reference | 0 volts | 4.75 volts | 5 volts |
The drive motor generator battery control module is also referred to as the battery energy control module (BECM). The BECM will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the BECM to the hybrid powertrain control module (HPCM) through the Hybrid LAN communication circuit. The HPCM is the host controller for diagnostic trouble code (DTC) information.
The drive motor generator battery has four hybrid battery temperature sensors. The hybrid battery temperature sensors are located on the top of the hybrid batteries. The temperature sensor is a variable resistor that measures the temperature of the hybrid batteries. The control module supplies 5 volts to the signal circuit and a ground for the low reference circuit. The hybrid battery 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 BECM uses the battery temperature sensors to determine the hybrid battery temperature to control the battery cooling fan operation.
• | The vehicle power mode is RUN. |
• | Accessory voltage is 9-18 volts. |
The hybrid battery temperature sensor is in normal operating range, but is at least 15°C (27°F) different from the other 3 sensors.
The hybrid battery temperature is greater than 95°C (203°F) and at least one other temperature sensor is less than 70°C (158°F).
The hybrid battery temperature is less than -40°C (-40°F).
• | When two or more sensors fail, the drive motor generator battery sends a message to the HPCM to reduce the power use limit to 50 percent and the battery vent fan will default to run. |
• | If all four sensors fail, the state of charge (SOC) will be considered invalid. |
• | DTCs P0A9C, P0A9D, P0A9E, P0AC6, P0AC7, P0AC8, P0ACB, P0ACC, P0ACD, P0AE9, P0AEB, and P0AEA are Type B DTCs. |
DTCs P0A9C, P0A9D, P0A9E, P0AC6, P0AC7, P0AC8, P0ACB, P0ACC, P0ACD, P0AE9, P0AEB, and P0AEA are Type B DTCs.
Hybrid Energy Storage Schematics
Control Module References for scan tool information
EL-48900 HEV Safety Kit
⇒ | If any of the listed DTCs are set, repair them first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle . |
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" Insulation gloves rated at 1000V with leather protectors - Visually and functionally inspect the gloves before use. - Wear the Insulation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.
⇒ | If obstructed, remove or repair as needed for proper air flow. |
⇒ | If fan or blades are damaged replace the battery vent fan. |
⇒ | If all four temperature sensors are not approximately the same value, continue to next step. |
⇒ | If all four temperature sensors are approximately the same value, the temperature sensors and control module are not at fault. Allow the temperature of the hybrid batteries to stabilize by letting the vehicle stand at room temperature, This could take 4 to 8 hours. Inspect the internal foam seals for damage or if missing and repair as needed. Verify proper cooling fan operation and air flow. |
⇒ | If greater than 500 ohms, replace the drive motor battery sensor module wiring harness assembly. |
⇒ | If less than 500 ohms, replace the drive motor generator battery control module and re-install the four temperature sensors. Refer to Generator Battery Temperature Sensor Location for the proper locations. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References for drive motor generator battery control module replacement, setup and programming |