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Makes 🢒 Pontiac 🢒 2006 🢒 GTO 🢒 Accessories 🢒 Theft Deterrent 🢒 Theft Deterrent System Inoperative

Circuit Operation

The theft deterrent system has 4 main components that require a valid code and linking between each other:

    • Remote coded key
    • Body control module (BCM)
    • Powertrain interface module (PIM)
    • Engine control module (ECM)

The BCM requires a valid code from the remote coded key via either the remote key receiver or the slip ring. The BCM transmits that it has received a valid code from the remote coded key out on the serial data bus. Upon the ignition being turned to ON, the PIM and ECM energize and the ECM sends continuous requests to the PIM for a valid code. The PIM will only respond to the ECM with a valid code once it has received a valid code from the BCM. When the ECM receives this valid code, the ECM allows the engine to crank and start. For further information refer to Theft Systems Description and Operation .

Test Description

  1. This step tests if there is power, ground and serial communications to the BCM.

  2. This step tests if the door locks operate using the remote coded key. Verifies if the remote coded key and the receiver are correctly linked to the BCM.

    3.

  3. This step tests if the turn signal indicators operate when the remote coded key buttons are pressed.

  4. This step tests if the BCM is producing a signal to activate the turn signal lamps when the LOCK or UNLOCK button is pressed on the remote coded key. Isolates whether the BCM or the circuits for the turn signal lamp are at fault.

  5. This step tests if the theft deterrent system is armed. Isolates whether the BCM is at fault.

  6. This step tests if the security status indicator will illuminate when instructed through the scan tool. Isolates whether the BCM is at fault.

    7.

  7. This step tests if the BCM is supplying a ground circuit to the instrument cluster to illuminate the security status indicator. Isolates whether the BCM is at fault.

  8. This step tests for continuity in circuit 264. Isolates whether circuit 264 or the instrument cluster is at fault.

  9. This step tests if when the UNLOCK button on the remote coded key is pressed, that the system disarms.

    10.

  10. This step tests if the BCM automatically arms the system after 30 seconds if the remote coded key is not inserted into the ignition switch.

  11. This step tests the operation of the slip ring.

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

1

  1. Connect the scan tool to the data link connector.
  2. Close all the doors but do not lock.
  3. On the scan tool select: F4: Body/Body Control Module and follow the scan tool prompts

Does the scan tool display the BCM's system identification which includes Identifier, Part Number and Software Version?

Go to Step 2

Go to Diagnostic Starting Point - Computer/Integrating Systems

2

Important: In this step, monitor the turn signal lamp indicators on the instrument cluster

  1. Remove the remote coded key from the ignition switch.
  2. Press the LOCK button on the remote coded key.

Do the doors lock?

Go to Step 3

Go to Diagnostic Starting Point - Keyless Entry

3

In Step 2, did the turn signal lamp indicators flash?

Go to Step 5

Go to Step 4

4

  1. Using a test lamp, probe both the left and right turn signal indicator lamp outputs of the Body Control Module, connector C1 terminal 3 and 4, to ground.
  2. Press the UNLOCK then the LOCK button on the remote coded key.

Does the test lamp illuminate momentarily on both outputs?

Go to Step 17

Go to Step 18

5

Does the security status indicator flash?

Go to Step 10

Go to Step 6

6

  1. Wait 30 seconds.
  2. On the scan tool select :F4: Body/Body Control Module/F2: Data Display/Theft Deterrent.
  3. Scroll to Security Status. Ensure all doors are closed

Does the scan tool display Armed?

Go to Step 7

Go to Step 18

7

  1. Insert the remote coded key into the ignition cylinder and turn to the ON position.
  2. On the scan tool select:F4: Miscellaneous Tests/Security System/F0: Security LED.
  3. On the scan tool press the ON soft key.

Does the security status indicator illuminate for 5 seconds?

Go to Step 18

Go to Step 8

8

Using a fused jumper wire, connect the security status indicator output of the BCM, connector C1 terminal 21, to ground.

Does the security status indicator illuminate?

Go to Step 18

Go to Step 9

9

Using a fused jumper wire, connect the security status indicator input to the Instrument Cluster Assembly, connector C1 terminal 14, to ground.

Does the security status indicator illuminate?

Go to Step 19

Go to Step 20

10

With the key removed from the ignition switch, press the UNLOCK button on the remote coded key

Does the security status indicator extinguish?

Go to Step 11

Go to Step 18

11

On the scan tool scroll to Security Status.

Does Security Status change to Passive Armed after 30 seconds?

Go to Step 12

Go to Step 18

12

  1. The scan tool displays the following:
    2. • Security Status is Passive Armed.
    • Slip Ring Enable is Off.
  2. Insert the remote coded key into the ignition switch and turn to ON.

Does the scan tool display the following?

    • Security Status changes to Disarmed.
    • Slip Ring Enable momentarily changes from OFF to ON and then back to OFF.

Go to Diagnostic Starting Point - Computer/Integrating Systems for further diagnostic information related to the Powertrain Interface Module.

Go to Step 13

13
  1. Using the scan tool select: F4: Body/Body Control Module/F2: Data Display/Theft Deterrent.
  2. On the scan tool scroll to Ignition Switch. With the ignition in the ON position, the scan tool displays Ignition Switch ON.
  3. Turn the ignition key to OFF. The scan tool displays Ignition Switch OFF.

Does the scan tool display as described?

Go to Step 14

Go to Ignition Switch Diagnostics

14
  1. Isolate the remote coded key contact pin using a thin piece of paper.
  2. Insert the key into the ignition switch and turn the ignition switch to the ON position.
  3. Measure the DC voltage between the ignition switch's slip ring and ground.

Does the multimeter display battery voltage?

Go to Step 15

Go to Step 16

15

Measure the AC voltage between the slip ring and a ground.

Does the multimeter display fluctuate between 0 to 10 V AC?

System OK

Go to Step 18

16
  1. Turn the ignition OFF and remove the key.
  2. Check for continuity between the slip ring input of the BCM, connector C2 pin 7 and the Ignition Switch Assembly connector C2 pin A.

Does the multimeter display continuity?

Go to Step 18

Go to Step 17

17

Repair the turn signal indicator output circuit of the BCM.

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

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18

Replace the BCM. Refer to Body Control Module Replacement .

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

--

19

Repair the security status indicator control circuit between the BCM and the Instrument Cluster Assembly.

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

--

20

Replace the Instrument Cluster Assembly. Refer to Instrument Cluster Replacement .

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

--

21

Repair the circuit between the slip ring input of the BCM, connector C2 terminal 7 and the Ignition Switch Assembly connector C2 terminal A.

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

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