For 1990-2009 cars only
Diagnostic Instructions
| • | 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. |
DTC Descriptor
DTC P0AA1: Hybrid Battery Positive Contactor Circuit Stuck ClosedCircuit/System Description
The battery energy control module (BECM) monitors to detect a fault with the contactor.
The Link Voltage is the voltage on the 36 volt cable between the SGCM and the BECM, Pack voltage is the sum of all module voltages. refer to Hybrid Energy Storage Schematics for detailed information.
Conditions for Running the DTC
Ignition to OFF, transition from contactor closed to contactor open.
Conditions for Setting the DTC
Absolute Value (Pack Voltage - Link Voltage) is less than 1 volt.
Action Taken When the DTC Sets
The hybrid system is disabled.
Conditions for Clearing the DTC
| • | State = Run or Service or Powerdown. |
| • | Pack current is less than -0.1 amps. |
| • | Contactor state = Open. |
| • | Contactor status = Open Service Disconnect. |
| • | Current sensor DTCs = Passed. |
| • | Pack voltage reading = Valid. |
| • | Pack voltage DTCs = Passed. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Starter/Generator Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- If there are any current DTCs set, diagnose those first, including any clearing any codes.
- Cycle the ignition switch from OFF to RUN several times, allowing at least 5 seconds after each transition from Ignition OFF to RUN.
| ⇒ | If the DTC resets, replace the BECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for BECM replacement, setup, and programming.
