• | 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 |
---|---|---|---|---|
Disconnect Lever High Voltage Fuse | -- | P0A95*, P0ABC*, P1A20** | -- | -- |
High Voltage Monitor Positive | P1AE7 | P0ABB | -- | -- |
High Voltage Monitor Negative | P1AE7 | P0ABB | -- | -- |
*DTC P0A95 and P0ABC will only set if the HV contactors are closed when the fuse opens. **DTC P1A20 will set if the fuse is open when the ignition is turned ON. |
The BECM has several methods of monitoring the total voltage values of the hybrid batteries. The BECM monitors the calculated battery voltage and the terminal voltage. The calculated voltage represents the sum of the voltages from the 20 individual battery measurements, and the terminal voltage represents the total DC bus voltage as measured on the output side of the high voltage contactor relays. The BECM compares these two voltage readings and looks for a difference. The BECM also monitors the terminal voltage for both over voltage and under voltage conditions.
• | The ignition is ON. |
• | The 12 V battery voltage is 9-18 V. |
• | The HV contactors are closed. |
The BECM detects a 50 V difference between the hybrid battery pack calculated voltage and the hybrid battery terminal voltage for 7 seconds.
The BECM detects the terminal voltage is less than 50 V for 3 seconds.
The BECM detects the terminal voltage is greater than 430 V for 3 seconds.
The battery vent fan is commanded to high speed.
DTCs P0ABB, P0ABC, and P0ABD are type A DTCs.
Hybrid Energy Storage Schematics
Drive Motor Battery System Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
• | EL-48571 High Voltage Battery Pin Out Box |
• | EL-48900 HEV Safety Kit |
Ignition ON, engine OFF, observe the scan tool Hybrid Battery Pack Calculated and Hybrid Battery Terminal parameters. The readings should be between 169 and 408 Volts, and should be within 50 Volts of each other.
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 DTC P0ABC is set, diagnose that DTC first. |
⇒ | If not within the specified range, test the 300 V reference circuits for an open/high resistance between the BECM X5 and HV terminals. If all circuits test normal, replace the BECM. |
⇒ | If not within the specified range, replace the drive motor battery assembly. |
⇒ | If any of the specified DTCs are set, diagnose those DTCs first. |
⇒ | If less than the specified value, replace the drive motor generator battery. |
⇒ | If greater than the specified value, replace the HV positive contactor relay. |
⇒ | If greater than the specified value, replace the HV negative relay. |
⇒ | Replace any damaged or open components as required. |
⇒ | Replace any damaged or open components as required. |
⇒ | Replace any damaged or open components as required. |
⇒ | If greater than the specified range, replace the drive motor generator battery. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References - for BECM replacement, setup and programming. |