B1325
DTC B1325
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (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 B1325 03
- Device Power Circuit Voltage Below Threshold
DTC B1325 07
- Device Power Circuit Voltage Above Threshold
Diagnostic Fault Information
Circuit/System Description
The following control modules monitor the battery voltage on the battery positive (B+) voltage circuit:
* Body control module (BCM)
* Instrument panel cluster (IPC)
* Passenger presence system (PPS)
* Radio
* Sensing and diagnostic module (SDM)
* Theft deterrent module (TDM)
If any of the modules listed detects that the battery voltage is out of range, it will set DTC B1325.
Conditions for Running the DTC
* The ignition is ON.
* The battery voltage supplied to the control modules is in the range of 7-26 volts.
Conditions for Setting the DTC
B1325 03
The control module detects that the system voltage is less than 9 volts for 5 seconds.
B1325 07
The control module detects that the system voltage is greater than 18 volts for 5 seconds.
Action Taken When the DTC Sets
The control module immediately disables all outputs when an out of range voltage condition has been detected, with the exception of GMLAN and the run/crank relay, which is disabled after a 3 minute delay.
Conditions for Clearing the DTC
The DTC passes when the malfunction is no longer present.
Diagnostic Aids
* A high or low voltage value in multiple modules indicates a concern in the charging system.
* Overcharging with a battery charger can cause this DTC to set.
Reference Information
Schematic Reference
* Body Control System Schematics (Electrical Diagrams)
* Instrument Cluster Schematics (Instrument Cluster Schematics)
* SIR Schematics ([1][2]Air Bag Systems)
* Radio/Navigation System Schematics (Radio/Navigation System Schematics)
* Immobilizer Schematics (Immobilizer Schematics)
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 (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
Circuit/System Testing
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 volts.
• If not within the specified range, refer to Charging System Test (Charging System Test).
Warning: Refer to SIR Warning (SIR Warning) , if DTC B1325 is set in the SDM.
2. Ignition OFF, disconnect the harness connectors at the appropriate module.
3. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the following ground circuit terminals and ground:
* Terminal 4 (TDM)
* Terminal 6 (IPC)
* Terminal 31 (SDM)
* Terminal 8 X1 (Radio)
* Terminal D X1 (PPS)
* Terminal 12 X1 (BCM)
* Terminal 13 X2 (BCM)
* Terminal E12 X4 (BCM)
* Terminal 9 X1 (BCM w/LAT/LE5/LY7)
• If greater than the specified range, test the ground circuit for an open/high resistance.
4. Verify that a test lamp illuminates between the following B+ circuit terminals and ground:
* Terminal 1 (SDM)
* Terminal 2 (TDM)
* Terminal 14 (IPC)
* Terminal 1 X1 (Radio)
* Terminal D12 X3 (BCM)
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
5. If the DTC is set in the PPS, verify that a test lamp illuminates between the ignition circuit terminal A X1 and ground.
• If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
6. If all circuits test normal, replace the appropriate module.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for the appropriate module replacement, setup, and programming.