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B1325




DTC B1325

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 B1325 03
- Device Power 1 Circuit Voltage Below Threshold

DTC B1325 07
- Device Power 1 Circuit Voltage Above Threshold

Diagnostic Fault Information





Circuit/System Description

The body control module (BCM) monitors the battery voltage through the battery voltage signal circuit. If the BCM senses that battery voltage is outside of its normal range, DTC B1325 will set. Damage to components, and incorrect data may occur when the voltage is out of range.

Conditions for Running the DTC

* The voltage supplied to the BCM are in the range of 7-26 V.
* The ignition is ON.
* The engine is running.

Conditions for Setting the DTC

B1325 03

The BCM detects a system voltage less than 9 V for 5 seconds.

B1325 07

The BCM detects a system voltage greater than 18 V for 5 seconds.

Action Taken When the DTC Sets

* The BCM immediately disables all outputs when an out of range system voltage condition has been detected, with the exception of serial data, which are disabled after a 3 minute delay.
* The setting of other DTCs is inhibited.

Conditions for Clearing the DTC

The DTC clears when the system voltage returns to a normal range.

Diagnostic Aids

* A high or low voltage DTC set in multiple modules indicates a concern in the charging system.
* A possible cause of this DTC could be overcharging with a battery charger or jump starting.
* A high or low voltage value in multiple modules indicates a concern in the charging system.

Reference Information
Schematic Reference

Body Control System Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
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 measure and record the voltage at the battery terminals. Verify that the battery voltage is 12.6-15.5 V.

If the battery voltage is not within the specified range, refer to Charging System Test (Charging System Test)

2. Engine running, observe the scan tool BCM Battery Positive Voltage parameter. The reading should be between 12.6 and 15.5 V.

Circuit/System Testing

1. Ignition OFF. Disconnect the harness connectors at the BCM.
2. Test for less than 3.0 Ohms between the ground circuits terminals listed below and ground.

* Terminal 12 X1
* Terminal E12 X4

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

3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminals listed below and ground.

* Terminal D6 X3
* Terminal D1 X3
* Terminal D12 X3

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

4. If all the circuits test 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.