Cellular Communications System Diagnosis

DTC B1983 Source/Battery Voltage Low:

Refer to Cellular Telephone Schematics. Electrical Diagrams

CIRCUIT DESCRIPTION
Battery Positive Voltage (B+) is supplied to the cellular telephone module connector on CKT 2240 (ORN) at terminals 4 and 16. The module monitors this voltage to determine if it is within a valid operating range.

CONDITIONS FOR SETTING DTC
The Battery Positive Voltage (B+) level falls below 9 volts for approximately 1.2 seconds or more.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a DTC B1953 in the module memory.
^ The module does not respond to any inputs when the voltage is less than 9 volts
^ No driver warning message will be displayed for this DTC.
^ Other module DTCs will not set while DTC B1983 is current.

CONDITIONS FOR CLEARING DTC
^ A current DTC clears (status changes from current to history) if the battery positive voltage (B+) level rises above 9.5 volts for approximately 1.2 seconds.
^ Use the On-Board clearing DTCs feature.
^ A history DTC clears after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Use the On-Board clearing DTC's feature.
^ Use a scan tool.

DIAGNOSTIC AIDS
The module will not check for low Battery Positive Voltage (B+) during and for 2 seconds following the engine CRANK mode. This delay ensures that DTC B1983 will not erroneously set.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
1. Perform the Diagnostic System Check before continuing with the diagnosis of this DTC.
4. Checks that DTC was not erroneously set.
5. Determines whether the malfunction is in the charging system or the module which set the DTC.
7. Clear all DTCs after the repair procedure is complete.