B1390

DTC B1390

Circuit Description

The body control module (BCM) has an internal battery voltage sensor and a reference voltage. The BCM compares 2 of the voltages via the 2 battery positive voltage circuits every 300 milliseconds.

DTC Descriptor

This diagnostic procedure supports the following DTC:
DTC B1390 Device Voltage Reference Input Circuit

Conditions for Running the DTC

This DTC will run only if the BCM has power and ground. This DTC will execute regardless of the source voltage.

Conditions for Setting the DTC

This code shall be set after 10 consecutive readings that the 2 battery positive voltages differ by one volt or greater.

Action Taken When the DTC Sets

All writes to the electrically erasable programmable read only memory (EEPROM) will be suspended. All loss of communication and low/high voltage DTC codes are suspended.

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.

Test Description










The numbers below refer to the step numbers on the diagnostic table.

3. This step tests for the proper voltage at battery positive voltage sense circuits of the BCM. If voltages are not within the proper operating range, the voltage sense circuits needs to be tested.
4. This step tests the ground sense circuit of the BCM.
5. This step tests for the proper voltage of the battery sense circuits to the BCM. If voltage is not within the proper operating range, the battery positive voltage and ground circuits of the BCM need to be tested.