Diagnostic Instructions
DTC Descriptors
DTC B1325 03: Device Power Circuit Voltage Below Threshold
DTC B1325 07: Device Power Circuit Voltage Above Threshold
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
B+
| B1325 03
| B1325 03
| --
| --
|
Ground
| --
| B1325 03
| --
| --
|
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) |
| • | 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 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
Connector End View Reference
Component Connector End Views
Description and Operation
Charging System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- 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.
Warning: Refer to SIR Warning in the Preface section.
- Ignition OFF, disconnect the harness connectors at the appropriate module.
- 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 9 X1 (BCM w/LAT/LE5/LY7) |
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Verify that a test lamp illuminates between the following B+ circuit terminals and ground:
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
- 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. |
- If all circuits test normal, replace the appropriate module.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for the appropriate module replacement, setup, and programming.
