Entertainment System Diagnosis

Diagnostic Chart:

CIRCUIT DESCRIPTION
Battery power is supplied to the Integrated Radio Controller (IRC) by the battery guard relay on circuit A52. The Body Control Module (BCM) controls the output to the battery guard relay. The IRC monitors the voltage to determine if it is within a valid operating range.

CONDITIONS FOR SETTING THE DTC
DTC B1983 will set when the source voltage to the IRC falls below 9.5 volts for 1.2 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a DTC B1983 in the IRC memory.
^ A current DTC B1983 prevents the IRC from setting a Class 2 Loss of Serial Data, short to ground or battery DTC.
^ The IRC will not respond to any manual or memory inputs when the voltage is below 9.5 volts.
^ No driver warning message will be displayed for this DTC.

CONDITIONS FOR CLEARING THE DTC
^ DTC B1983 will clear when the source voltage is above 9.5 volts for 1.2 seconds.
^ DTC B1983 can also be cleared by using a scan tool.

DIAGNOSTIC AIDS
The IRC will not check the voltage level on this circuit for approximately 2 seconds following the engine crank mode. This insures that DTC B1983 will not set erroneously.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. Clear all DTCs and cycle the ignition to check that the DTC did not falsely set.
3. It the vehicle is not cranking properly, the battery may be at fault. Low battery voltage can set this DTC.