DTC B1447 RHD
Diagnostic Instructions
DTC Descriptor
DTC B1447 03: Backup Battery Voltage Too Low
DTC B1447 04: Backup Battery Circuit Open
DTC B1447 07: Backup Battery Voltage Too High
Circuit/System Description
The Back-up Battery provides voltage to the communication interface module , to be able to successfully place a call in the event of a main battery disconnect during a collision event.
Conditions for Running the DTC
| • | Ignition is in the RUN or ACC position. |
| • | System voltage is between 9.5 and 15.5 volts. |
| • | The above conditions are present for greater than 10 seconds. |
Conditions for Setting the DTC
The communication interface module detects no voltage from the back-up battery.
Action Taken When the DTC Sets
| • | The communication interface module module will be unable to place a call in the event of a main battery disconnect during a collision event. |
| • | The communication interface module module commands the red LED ON. |
Conditions for Clearing the DTC
| • | A current DTC B1447 will clear when the CIM detects voltage from the back-up battery. |
| • | The history DTC will clear after 50 fault-free ignition cycles. |
Diagnostic Aids
Note: DTC B1447 may set if the communication interface module has been incorrectly disconnected or serviced. When disconnecting the communication interface module, disconnect the harness connector X1 at the communication interface module
prior to disconnecting any other harness connectors. This will ensure the back-up battery is preserved when voltage is removed from the communication interface module.
Reference Information
Schematic Reference
Telematics Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Telematics Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector X1 at the comunication interface module.
- Test for greater than 15.5 volts between terminals 13 and 14.
| ⇒ | If less than specified value, test the battery backup supply voltage circuit and battery backup low reference circuit for an open/high resistance, short to ground or short to voltage. If the circuits test normal, replace the back-up battery. |
- If all circuits test normal, replace the comunication interface module.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
