GM Service Manual Online
For 1990-2009 cars only

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 it receives over the class 2 communication circuit, the radio will operate normally.

Conditions for Running the DTC

    • The DTC is run when the radio is turned from OFF to ON.
    • Battery voltage is between 9 and 16 volts.

Conditions for Setting the DTC

Installing a radio from a different vehicle platform or installing a new body control module (BCM) and not entering the correct setup information with the scan tool.

Action Taken When the DTC Sets

The radio does not function properly. The radio displays "CAL".

Conditions for Clearing the DTC

    • Installing a radio from another vehicle of the same platform or a new radio of the same platform.
    • 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 scan tool will automatically clear after 100 consecutive fault free ignition cycles.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Clear all DTCs and cycle the ignition in order to verify that the DTC did not falsely set.

  2. Clear all DTCs after the repair procedure is complete.

Step

Action

Yes

No

1

Did you perform the Radio/Audio System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Radio/Audio System

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool, perform the radio setup procedure. Refer to Radio Setup .
  4. Turn OFF the ignition.
  5. Turn ON the ignition, with the engine OFF.

Does the DTC reset?

Go to Step 3

System OK

3

Important:: Perform the setup procedure after replacing the radio.

Replace the radio. Refer to Radio Replacement and to Radio Setup .

Did you complete the replacement?

System OK

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