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B1517




DTC B1517

Diagnostic Instructions

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

DTC Descriptors
DTC B1517 5A
- Battery Voltage Plausibility Failure

Diagnostic Fault Information






Typical Scan Tool Data










Circuit/System Description

The body control module (BCM) has two circuits for monitoring vehicle system voltage. The circuits are supplied by the IBCM 1 fuse and the BATT SENSE fuse. The BCM monitors the system voltage on the two B+ circuits to ensure that the voltage stays within the normal range. Damage to components, and incorrect data may occur when the voltage is out of range.

Conditions for Running the DTC

* The BCM has power and ground.
* The ignition is not in the START position.

Conditions for Setting the DTC

The voltage of the two BCM battery sense circuits differs by 2 V for 10 seconds.

Action Taken When the DTC Sets

The instrument panel cluster (IPC) illuminates the charge indicator.

Conditions for Clearing the DTC

* The DTC will pass when the condition is no longer present.
* A history DTC will clear after 50 consecutive ignition cycles have occurred without a malfunction.

Diagnostic Aids

* A high or low voltage DTC in multiple modules indicates a concern in the charging system.
* This DTC may be set by overcharging with a battery charger, or jump by starting.

Reference Information
Schematic Reference

Starting and Charging Schematics Electrical Diagrams
Connector End View Reference

Component Connector End Views Connector End Views By Name
Description and Operation

Charging System Description and Operation Description and Operation
Electrical Information Reference

* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Programming and Relearning for scan tool information

Circuit/System Verification

1. Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 V.

If not within the specified range, refer to Charging System Test Charging System Test.

2. Observe the scan tool BCM Battery Voltage Signal parameter and the Batt. Voltage High Res. parameter. The reading for both parameters should be between 12.6 and 15.0 Volts, and should be within 2 Volts of each other.

Circuit/System Testing

1. Verify that a test lamp illuminates between the ONSTAR fuse in the BCM and ground.

If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

2. Ignition OFF, disconnect the harness connectors at the BCM.
3. Ignition OFF, test for less than 5 Ohms of resistance between the ground circuit terminals listed below and ground.

* Terminal 9 X1
* Terminal E12 X4

If greater than the specified range, test the ground circuit for an open/high resistance.

4. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground.

* Terminal 11 X1
* Terminal D12 X3

If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

5. If all circuits tests normal, replace the BCM.

Repair Instructions

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

Control Module References Programming and Relearning for BCM replacement, setup, and programming.