P0AC2
DTC P0AC0, P0AC1, P0AC2, or P1A07
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (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 P0AC0
- Hybrid Battery Current Sensor Performance
DTC P0AC1
- Hybrid Battery Current Sensor Circuit Low Voltage
DTC P0AC2
- Hybrid Battery Current Sensor Circuit High Voltage
DTC P1A07
- Battery Energy Control Module 5-Volt Reference Circuit
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The hybrid battery current sensor is mounted inside the drive motor generator battery assembly. The positive high voltage (HV) cable that goes to the positive contactor relay passes through the current sensor. The current sensor detects the amperage that flows in and out of the hybrid batteries. The drive motor generator battery control module supplies and monitors a 5 volts reference signal to the current sensor. The current sensor returns a signal between 0 and 5 volts to the drive motor generator battery control module. The current sensor signal is in proportion to the amperage going in and out of the drive motor generator battery. A signal voltage of the current sensor greater than 2.5 volts indicates that the drive motor generator battery is being discharged and a signal voltage less than 2.5 volts indicates charging. The hybrid battery current sensor has 3 measurement ranges in order to maintain accuracy. The ranges are low, medium and high. The measurement ranges of the current sensor have some overlap with each other. The low range measures from -22 to +22 amps. The medium range measures from -52 to +52 amps. The high range measures from -250 to +250 amps.
Conditions for Running the DTC
* The ignition is ON.
* The 12 volt battery is 9-18 volts.
Conditions for Setting the DTC
P0AC0
One of the following conditions exists:
* The drive motor generator battery control module detects greater than 5 amps on the current sensor after a successful HV system power down and after the contactors have opened.
* The drive motor generator battery control module detects an increase in total pack voltage greater than 10 volts and the current sensor measures less than a 0.5 amp increase.
* The drive motor generator battery control module detects less than 20 amps on the high range sensor and the difference between the high range current measurement and the medium range current measurement is greater than 20 amps for 3 seconds.
* The drive motor generator battery control module detects less than 20 amps on the high range sensor and the difference between the high range current measurement and the low range current measurement is greater than 4 amps for 3 seconds.
P0AC1
The drive motor generator battery control module detects that the current sensor high range is greater than +200 amps and the current sensor medium range is greater than +52 amps and the current sensor low range is greater than +22 amps for 3 seconds.
P0AC2
The drive motor generator battery control module detects that the current sensor high range is less than -200 amps and the current sensor medium range is less than -52 amps and the current sensor low range is greater than -22 amps for 3 seconds.
P1A07
The drive motor generator battery control module detects less than 4.8 volts or greater than 5.2 volts on the 5 volt reference circuit.
Action Taken When the DTC Sets
* The driver information center (DIC) displays the SERVICE HYBRID SYSTEM message.
* State of charge goes to invalid.
* The drive motor generator battery control module sends a message to the HPCM requesting that the hybrid battery power limit be set to 3 kilowatts, resulting in minimal hybrid function.
* DTC P0AC0, P0AC1, P0AC2, and P1A07 are type A DTCs.
Conditions for Clearing the DTC
DTC P0AC0, P0AC1, P0AC2, and P1A07 are type A 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 Battery System Description (Drive Motor Battery System Description)
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-48900 HEV Safety Kit
Circuit/System Verification
Ignition ON, observe the scan tool Calc. Hybrid Batt. Current parameter. The reading should be between -200 and +200 amps, and change with the amount of current draw on the drive motor generator battery.
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.
1. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling).
2. Remove the drive motor generator battery case upper cover, front cover and right side cover.
3. Ignition OFF, connect the 12 V battery.
4. Disconnect the harness connector at the current sensor.
Note: The scan tool must be disconnected and the ignition switch OFF for 30 seconds for proper test results.
5. Ignition OFF, test for less than 5 ohms between low the reference circuit terminal 2 and ground.
• If greater than the specified range, test the low reference circuit for a open/high resistance. If the circuit tests normal, replace the drive motor generator battery control module.
6. Ignition ON, test for 4.9-5.1 V between the 5 V reference circuit terminal 1 and ground.
• If less than the specified range, test the circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the drive motor generator battery control module.
• If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the drive motor generator battery control module.
7. Ignition ON, test for 4.7-5.3 V between the signal circuit terminal 3 and ground.
• If less than the specified range, test the circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the drive motor generator battery control module.
• If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the drive motor generator battery control module.
8. If all circuits test normal, replace the current sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement (Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement)
* Drive Motor Battery Current Sensor Replacement (Drive Motor Battery Current Sensor Replacement)
* Drive Motor Battery Sensor Module Wiring Harness Replacement (Drive Motor Battery Sensor Module Wiring Harness Replacement)
* Control Module References (Programming and Relearning) for control module replacement, setup and programming.