GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The theft deterrent control module checks memory to see if the Learn Coded Key setting is on. If so, the theft deterrent control module sets this DTC.

Running the DTC

The theft deterrent control module must see the ignition switch input. The theft deterrent control module can not have a B1327 set as a current DTC.

Conditions for Setting the DTC

If the Learn Coded Key setting is on, the theft deterrent control module sets this DTC.

Action Taken When the DTC Sets

The theft deterrent control module will learn the key code. The theft deterrent control module will illuminate the security indicator.

Conditions for Clearing the MIL/DTC

The theft deterrent control module clears the current status of the DTC when it does not see the Learn Coded Key setting as on. The DTC will still be retrieved as current until the ignition switch is cycled. The DTC will become a history DTC at that time.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. To set this code, a key with a working transponder was read by the theft deterrent control module. For that key to operate the vehicle, a 10 Minute or 30 Minute Re-Learn Procedure must be performed.

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

Connector End View Reference: Theft Deterrent System Connector End Views

1

Did you perform A Diagnostic System Check - Theft Deterrent?

Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

Important: If a 10 Minute or 30 Minute Re-Learn Procedure is performed, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys .

Perform the programming theft deterrent system components procedure. Refer to Programming Theft Deterrent System Components .

Is the procedure complete?

Go to Step 3

--

3

  1. Use a scan tool in order to clear the DTCs.
  2. Attempt to start the vehicle.

Does the DTC reset?

Go to Step 2

System OK