Circuit Description
Each time the ignition cycles from OFF to ON, the radio receives VIN data over the class 2 communication circuit. If the VIN data in the radio memory matches the VIN data the radio receives over the class 2 communication circuit, the radio will operate normally.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1780 Theft Lock Enabled
Conditions for Running the DTC
| • | The DTC is run when the radio is turned from OFF to ON. |
| • | Battery voltage is between 9-16 volts. |
Conditions for Setting the DTC
Installing a radio from another vehicle or installing a new body control module (BCM) and not entering the correct VIN information with the scan tool.
Action Taken When the DTC Sets
The radio does not function. The radio displays "LOC" or "LOCKED" .
Conditions for Clearing the DTC
| • | When installing a radio from another vehicle of the same platform, clear the VIN data using the scan tool. |
| • | Installing a new BCM setup properly with the correct VIN for that vehicle. |
The DTC status will turn to history when the above criteria is met. The scan tool can now clear the history DTC, or the DTC will clear automatically after 100 consecutive fault free ignition cycles.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
After clearing the DTCs and theft information, the radio relearns the VIN upon cycling the ignition switch.
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After completing the repair procedure, clear all DTCs.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check-Vehicle? | Go to Step 2 | |
Does the DTC Reset? | Go to Step 3 | System OK | |
Replace the radio. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | System OK | -- |
