P1AB0

DTC P1AB0

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P1AB0
- Battery Pack Over Current

Circuit/System Description

The engine control module (ECM) monitors the hybrid battery pack for a high current condition.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

Battery pack current is greater than 140 amps or less than -330 amps.

Action Taken When the DTC Sets

Hybrid system is disabled.

Conditions for Clearing the DTC

* Battery pack current is inside the threshold.
* Battery pack current = Valid
* Current sensor out of range diagnostics and performance (DTC P0AC0, P0AAC1, P0AC2, P1A48 and P1A49) = Not Fail

Diagnostic Aids

This diagnostic could occur in conjunction with a open hybrid battery fuse.

Special Tools

J 35616 GM Approved Terminal Test Kit

Circuit/System Testing

Caution: To help avoid personal injury, additional precautions must be taken prior to working on the generator control module or the generator starter. After removing the 36V battery cables from the generator battery, remove both engine wiring harness connectors from the generator control module. Wait at least 5 minutes and then remove the generator control module cover. Verify voltage levels at all 36V, 12V, and 3-phase connections, are less than 3 volts using a DMM before proceeding.

Important: Use the following list to identify the appropriate terminals to test:

* J-35616-65B for female terminals
* J-35616-64B for male terminals

1. Verify the DTC is set as current.

^ If the DTC is history refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids or diagnostic aids. Component Tests and General Diagnostics

2. Test the condition of the hybrid battery pack fuse, replace the fuse if open. To gain access refer to Hybrid Battery Service Disconnect/Connect.

^ If the hybrid battery fuse is open, test the 36-volt positive cable from the starter/generator control module (SGCM) to hybrid battery pack for a short to ground.

3. Test the 36-volt positive cable for an open or high resistance.

^ If there is an open or high resistance, replace the 36-volt positive cable.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

36-Volt Battery Positive Cable Replacement (Engine to Passenger Compartment)