Circuit Description
The body control module (BCM) has an internal voltage sensor with a dedicated circuit that monitors the battery positive voltage circuit to determine if it is below 18 volts.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1328 Device Power Circuit High
Conditions for Running the DTC
This DTC shall run only if no communication codes are set.
Conditions for Setting the DTC
The ignition positive voltage level is greater than 18 volts for approximately 1/2 second or more.
Action Taken When the DTC Sets
The BCM sets a DTC and disables the following state of health (SOH) DTCs:
| • | DTC U1096 |
| • | DTC U1255 |
| • | DTC U1300 |
| • | DTC U1301 |
The BCM illuminates the charge lamp indicator.
Conditions for Clearing the DTC
| • | The battery positive voltage level is less than 17.9 volts for approximately 1/2 second. |
| • | A history DTC clears after 100 malfunction-free ignition cycles. |
| • | The BCM receives the clear code command from the scan tool. |
Diagnostic Aids
This DTC may set when the vehicle is placed on a battery charger, on fast charge, for a long period of time.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
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? | 18 V | Go to Step 3 | Go to Step 4 |
3 | Measure the voltage across the battery terminals. Is the battery voltage greater than the specified value? | 18 V | Go to Charging System Test | Go to Step 4 |
4 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 5 | -- |
5 |
Does the DTC reset? | Go to Step 2 | System OK |
