Circuit Description
The control modules on this vehicle monitor the battery voltage through the battery positive voltage circuits.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1325 Device Power 1 Circuit
This vehicle has DTCs that include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .
DTC Symptom | DTC Symptom Descriptor |
|---|---|
03 | Voltage Below Threshold |
07 | Voltage Above Threshold |
Conditions for Running the DTC
The 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 a system voltage below 9 volts and the condition is present at least 5 seconds.
B1325 07
The control module detects a system voltage above 18 volts and the condition is present at least 5 seconds.
Action Taken When the DTC Sets
| • | The control module immediately disables all outputs when a high voltage condition is detected, with the exception of GMLAN and Crank relay that are disabled after a 3 minute delay. |
| • | The setting of other DTCs is inhibited. |
Conditions for Clearing the DTC
| • | A current DTC clears when the malfunction is no longer present. |
| • | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction. |
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Control Module References | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
2 |
Is the Battery Voltage Signal parameter displayed in the specified range? | 9-18 V | Go to Step 3 | Go to Step 4 | ||||||
3 | Is the DTC set as a current DTC? | -- | Go to Step 7 | Go to Testing for Intermittent Conditions and Poor Connections | ||||||
4 |
Is the measured value in the specified range? | 9-18 V | Go to Step 6 | Go to Step 5 | ||||||
5 | Test the battery positive voltage circuit for the following:
Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 9 | Go to Battery Inspection/Test | ||||||
6 | Test all ground circuits of the module for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 | ||||||
7 | Inspect for poor connections at the harness connector of the affected module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 8 | ||||||
8 | Replace the affected module. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
9 | Operate the system in order to verify the repair. Did you find and correct the condition? | -- | System OK | Go to Step 2 | ||||||
