• | 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 | Signal Performance |
---|---|---|---|---|
Fan Supply Voltage | P0A81 | P0A81 | P0BC1 | -- |
Fan Speed Control | P0A81 | P0A81 | P0BC1 | -- |
Fan Relay Control | P0BC1 | P0A81 | P0A81 | -- |
The drive motor generator battery is cooled by a drive motor battery vent fan motor. The battery vent fan motor and battery vent fan relay are located inside the drive motor generator battery assembly. B+ to the battery vent fan is provided from the battery vent fan relay when the drive motor generator battery control module (GBCM) supplies a ground to the battery vent fan relay. A grounding wire from the battery vent fan motor assembly completes the path to case ground. A 5 V circuit is provided from the battery vent fan motor assembly, to the GBCM. The GBCM uses a pulse width modulated (PWM) signal on the 5 V circuit to control the battery vent fan motor duty cycle. The battery vent fan motor also supplies an additional 5 V signal that indicates vent fan speed back to the GBCM, the lower the voltage the greater the fan speed. The GBCM uses 4 battery temperature sensors, one air inlet duct and one air outlet temperature sensor to control battery vent fan motor operation and speed.
• | The ignition is ON. |
• | The battery voltage is 9-18 V. |
• | The fan has transitioned from either ON to OFF or from OFF to ON. |
The fan speed control circuit is greater than 0.9 V for 1 second.
DTC P0BC1 is a type B DTC.
DTC P0BC1 is a type B DTC.
Drive Motor Generator Battery Cooling Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
EL-48900 HEV Safety Kit
Ignition ON, engine OFF, with scan tool, command the battery pack vent fan speed to 60 percent duty cycle. The battery vent fan should turn ON and run at a medium-high speed.
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. |
⇒ | If less than the specified value, replace the drive motor generator battery control module. |
⇒ | If the test lamp illuminates, test the vent fan relay control circuit for a short to ground. If the circuit tests normal, replace the drive motor generator battery control module. |
⇒ | If the test lamp illuminates, repair the short to B+ on the supply voltage circuit between the battery fan relay and the battery vent motor. If the circuit tests normal, test or replace the relay. |
⇒ | If the test lamp illuminates, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the drive motor generator battery control module. |
⇒ | If less than the specified value, replace the drive motor generator battery vent fan relay. |
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. |
⇒ | If not within the specified range, replace the relay. |
• | 1 and 3 |
• | 1 and 4 |
• | 2 and 3 |
• | 3 and 4 |
⇒ | If not the specified value, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References - for drive motor generator battery control module replacement, setup and programming. |