Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B1325 03 : Device Power 1 Circuit Voltage Below ThresholdDTC B1325 07: Device Power 1 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 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
Connector End View Reference
Description and Operation
Charging System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running measure and record the voltage at the battery terminals. Verify that the battery voltage is 12.6-15.5 V.
- Engine running, observe the scan tool BCM Battery Positive Voltage parameter. The reading should be between 12.6 and 15.5 V.
| ⇒ | If the battery voltage is not within the specified range, refer to Charging System Test |
Circuit/System Testing
- Ignition OFF. Disconnect the harness connectors at the BCM.
- Test for less than 3.0 Ω between the ground circuits terminals listed below and ground.
- Ignition ON, verify a test lamp illuminates between the B+ circuit terminals listed below and ground.
- If all the circuits test normal, replace the BCM.
| • | Terminal 12 X1 |
| • | Terminal E2 X4 |
| ⇒ | If greater than the specified value, test the ground circuit for an open/high resistance. |
| • | Terminal D6 X3 |
| • | Terminal D1 X3 |
| ⇒ | If test lamp did not illuminate, test the B+ circuits for a short to ground or an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for BCM replacement, setup, and programming.
