• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
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.
• | Ignition is in the RUN or ACC position. |
• | System voltage is between 9.5 and 15.5 volts. |
• | DTC B1447 is not set. |
The communication interface module detects that the back-up battery voltage has dropped below the minimum threshold value.
The communication interface module commands the red LED ON.
• | When the CIM detects the voltage of the back-up battery is above the minimum threshold value. |
• | The history DTC will clear after 50 fault-free ignition cycles. |
Note: Shorting the back-up battery positive voltage circuit to the back-up battery ground circuit or chassis ground will activate the internal circuit protection of the back-up battery , rendering the back-up battery inoperable.
Telematics Description and Operation
Control Module References for scan tool information
⇒ | 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. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for communication interface module replacement, setup and programming. |