P1A0E
DTC P1A0E, P1A0F, or P1A47
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC P1A0E
- Battery Energy Control Module Hybrid Battery Voltage Sensor Circuit Low Voltage
DTC P1A0F
- Battery Energy Control Module Hybrid Battery Voltage Sensor Circuit High Voltage
DTC P1A47
- Battery Energy Control Module Hybrid Battery Voltage Sensor Performance
Diagnostic Fault Information
Circuit/System Description
The drive motor generator battery control module will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the drive motor generator battery control module to the drive motor generator control module through the communication circuit. The drive motor generator control module is the host controller for diagnostic trouble code (DTC) information.
The hybrid battery assembly consists of 22 individual battery modules. Each battery module is rated at 12.0 V. The batteries are connected together in a series circuit. The drive motor generator battery control module monitors the hybrid battery voltage on every two batteries for a total of 22 locations, across the battery assembly. The drive motor generator battery control module determines the actual terminal voltage by monitoring the output voltage from the high voltage contactors. The drive motor generator battery control module also multiplies each individual battery voltage measurement by 22, and compares this calculation to the terminal voltage measurement.
The voltage sensor monitors the terminal voltage that flows out of the hybrid batteries. The drive motor generator battery control module compares the pack voltage the sum of all module voltages measurements received from the hybrid battery voltage senors to the terminal voltage to determine the voltage sensors are operating correctly.
Conditions for Running the DTC
* The vehicle power mode is RUN.
* Accessory voltage is 9-18 V.
* The HV contactors are closed.
Conditions for Setting the DTC
P1A0E
The drive motor generator battery control module detects the terminal voltage is less than 50 V for 1 second.
P1A0F
The drive motor generator battery control module detects the terminal voltage is greater than 435 V for 3 second.
P1A47
* Terminal voltage = VALID
* Individual module volts = VALID
* The drive motor generator battery control module detects a 50 V difference between the hybrid battery pack voltage and the hybrid battery terminal voltage for 3 seconds.
Action Taken When the DTC Sets
DTCs P1A0E, P1A0F and P1A47 are type B DTCs.
Conditions for Clearing the DTC
DTCs P1A0E, P1A0F and P1A47 are type B DTCs.
Reference Information
Schematic Reference
Hybrid Energy Storage Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Drive Motor Generator Battery Description (Drive Motor Generator Battery Identification Information)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Special Tools
* EL-48571 High Voltage Battery Pin Out Box
* EL-48900 HEV Safety Kit
Circuit/System Testing
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.
P1A47
1. Verify that DTC P1A0E is not set.
• If DTC is set, refer to DTC P0ABB, P0ABC, or P0ABD (P0ABB).
2. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling)
3. Disconnect the X2 harness connector at the drive motor generator battery control module.
4. Connect the EL-48900 to the X2 harness connector.
5. Install the high voltage manual disconnect lever
6. Insert the DMM probes into the EL-48900 test cavities. Measure and record the voltage of each battery by cycling the EL-48571 through each of the 22 switch positions. All voltages should be between 10-15 V and within 1.5 V of each other.
• If any of the voltage values are not within the specified range, replace the drive motor generator battery assembly.
7. If all circuits test normal, replace the drive motor generator battery control module.
P1A0E
1. Verify that DTC P0C77 or P1A20 is not set.
• If any of the specified DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code Descriptions).
2. Ignition ON, verify the scan tool Hybrid Battery Pack Calculated parameter is greater than 200 V.
3. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling).
4. Connect the 12 V battery.
5. Connect a DMM between the HV positive contactor terminals 2 and 5. Refer to Saturn Vue-Hybrid Battery Connections for terminal identification.
6. Ignition ON, engine OFF, with a scan tool, command the HV positive contactor closed. While the contactor is closed, test for less than 0.5 ohm.
• If greater than the specified range, replace the drive motor battery disconnect control module.
7. Connect a DMM between the HV negative contactor terminals 3 and 6. Refer to Saturn Vue-Hybrid Battery Connections for terminal identification.
8. Ignition ON, engine OFF, with a scan tool, command the HV negative contactor closed. While the contactor is closed, test for less than 0.5 ohm.
• If greater than the specified range, replace the drive motor battery disconnect control module.
9. Disconnect the X2 harness connector at the drive motor generator battery control module.
10. Connect the EL-48900 to the X2 harness connector.
11. Install the high voltage manual disconnect lever
12. Insert the DMM probes into the test cavities. Measure and record the voltage of each battery by cycling the EL-48900 through each of the 22 switch positions. All voltages should be between 10-15 V and within 1.5 V of each other.
• --> If any of the voltage values are not within the specified range, replace the drive motor generator battery assembly.
13. If all circuits test normal, replace the drive motor generator battery control module.
P1A0F
1. Ignition ON, verify the scan tool Hybrid Battery Pack Calculated parameter is less than 435 V.
• If greater than the specified range, replace the drive motor generator battery assembly.
2. If the parameter is less than 435 V, replace the drive motor generator battery control module.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Drive Motor Battery Disconnect Control Module Replacement (Drive Motor Battery Disconnect Control Module Replacement)
* Control Module References (Programming and Relearning) for drive motor generator battery control module replacement, setup and programming.