Circuit Description
The control modules on this vehicle monitor system voltage through the battery positive voltage circuits. Damage to components, and incorrect data can occur when the voltage is out of range. This vehicle has multiple modules that will set this DTC. For more information on which modules refer to Diagnostic Trouble Code (DTC) List - Vehicle
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1327 Device Power 1 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 9.0 volts for 1.2 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 to notify all other modules of low battery voltage. |
| • | The modules disable the setting of U codes and other DTCs. |
Conditions for Clearing the DTC
| • | The DTC will clear current status when the voltage is greater than 9.5 volts for 1.2 seconds. |
| • | A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | Use a scan tool. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Starting and Charging Schematics or Power Distribution Schematics in Wiring Systems Connector End View Reference: Computer/Integrating Systems Connector End Views in Computer/Integrating Systems. | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the scan tool indicate that DTC B1327 is current in more than 1 module? | -- | Go to Step 6 | Go to Step 3 |
3 |
Does the voltage measure greater than the specified value? | 9.4 V | Go to Step 11 | Go to Step 4 |
4 |
Does the voltage measure greater than the specified value? | 9.4 V | Go to Step 5 | Go to Battery Inspection/Test |
5 | Measure the voltage between the battery positive voltage circuit of the BCM and a good ground. Does the voltage measure greater than the specified value? | 9.4 V | Go to Step 9 | Go to Step 8 |
6 |
Does the voltage measure greater than the specified value? | 9.4 V | Go to Step 10 | Go to Step 7 |
7 | Measure the voltage between the battery positive voltage circuit of the BCM or module setting DTC B1327 and a good ground. Does the voltage measure greater than the specified value? | 9.4 V | Go to Step 9 | Go to Step 8 |
8 | Test the battery positive voltage circuit of the BCM or module setting DTC B1327 for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
9 | Test the ground circuit of the BCM or module setting DTC B1327 for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
10 | Inspect for poor connections at the harness connector of the BCM or module setting DTC B1327. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 |
11 | Replace the affected module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 3 | System OK |
