Circuit Description
The module has an internal voltage sensor with a dedicated circuit that checks the battery positive voltage and battery negative circuit voltage to determine if it is between 9-15.9 volts.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1327 Device Power 1 Circuit Low
Conditions for Running the DTC
This DTC shall run only if the module has power, ground and the ignition is not in START mode. This DTC shall execute regardless of the battery voltage.
Conditions for Setting the DTC
| • | This DTC shall be set as current when the voltage falls below 9 volts for 2 seconds. |
| • | When the vehicle exits START the module shall delay checking the voltage for 2 seconds. |
Action Taken When the DTC Sets
A message shall be sent out via class 2 and may illuminate the charge indicator.
Conditions for Clearing the MIL/DTC
| • | In order to clear the DTC from a current status the voltage shall be greater than 9.54 volts for 2 seconds. |
| • | DTC may be cleared with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Tests for the proper operation of the complete circuit.
-
Tests for the proper operation of the battery positive voltage circuit.
Step | Action | Value | Yes | No |
|---|---|---|---|---|
Schematic Reference: Body Control System Schematics Connector End View Reference: Power and Grounding Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate the battery voltage is greater than the specified value? | 9.5 V | Go to Step 7 | Go to Step 3 |
Does the voltage measure near or above the specified value? | 9.5 V | Go to Step 7 | Go to Step 4 | |
Measure the voltage from the battery positive voltage circuit of the module to a known good ground. Does the voltage measure near the specified value? | B+ | Go to Step 6 | Go to Step 5 | |
5 | Test the battery positive voltage circuit of the module for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 |
6 | Test the ground circuit of the module for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 8 |
7 | Inspect for poor connections at the harness connector of the 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 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
