B1328

CIRCUIT DESCRIPTION

Schematic:

The Dash Integration Module (DIM) has a designated circuit for monitoring vehicle system voltage. Also, other modules monitor system voltage. The DIM sends the system voltage status to other modules that do not monitor system voltage via Class 2 message. When the DIM sets B1390, the system voltage status sent to the modules will default to 12.9 Volts.

CONDITIONS FOR RUNNING THE DTC
The ignition switch is not in the OFF or CRANK mode.

CONDITIONS FOR SETTING THE DTC
This DTC will set as current when the voltage is greater than 15.9 volts for 1.2 seconds and DTC B1390 is not set current in the DIM.

ACTION TAKEN WHEN THE DTC SETS
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 less than 15.5 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 the ON-Board clearing DTCs feature.
^ Use a scan tool.

DIAGNOSTIC AIDS
The following conditions are independent of the DTC, but will occur with the DTC set current.
^ The battery charge indicator is illuminated on the instrument cluster.
^ The BATTERY VOLTS HIGH message is displayed on the Driver Information Center (DIC).

TEST DESCRIPTION

Step 1 - 7:

The numbers below refer to the step numbers on the diagnostic table.
3. Tests for the proper voltage at the DIM. If the voltage is not within the proper operating range, the charging system needs to be checked.
4. Tests for the proper voltage at the module setting the DTC B1328. If the voltage is not within the proper operating range, the charging system needs to be checked.