• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
12V B+ | B1325 03 | B1325 03 | B1325 07 | -- |
Ground | -- | B1325 03 | B1325 07 | -- |
The control modules on this vehicle monitor the battery voltage on the 12V battery positive (B+) voltage circuits. This vehicle has multiple modules that will set the DTC. For information about which modules, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
• | The 12V battery voltage supplied to the control modules is in the range of 7-26 volts. |
• | The engine is running. |
The control module detects that the 12V system voltage is less than 9 volts for 5 seconds.
The control module detects that the 12V system voltage is greater than 18 volts for 5 seconds.
• | The control module immediately disables all outputs when an out of range voltage condition has been detected, with the exception of GMLAN, which is disabled after a 3 minute delay. |
• | The setting of other DTCs is inhibited. |
The DTC clears when the malfunction is no longer present.
• | 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. |
Charging System Description and Operation
Control Module References for scan tool information
⇒ | If not within the specified range, refer to Charging System Test . |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the 12V B+ circuit for a short to ground or an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for the appropriate module replacement, setup, and programming.