If it has the key on the steering column the part you saw in the column is the theft deterrent module, the ring for the transponder key is part of it. He may be thinking of the earlier GMs that did have the TDM remote mounted in the dash. The TDM ties into the key-less entry system and the power-train module all through the CAN network in the truck. It works by sending out a pulse that sort of wakes the key up, then it reads the signal from the key and compares that to a list of valid keys for your truck (up to 10) If the key is valid it sends a signal to the PCM telling it that it can turn on the fuel pump and ignition and start the engine.
If you have key-less entry it works about the same except that the fob transmits a low power signal carrying the code to identify it as a valid fob.
Once the TDM is replaced it has to be programmed into the system with a scan tool, and a GM dealer terminal then the keys need to be relearned as well. Each TDM also has a unique code to ID it to the system which is why it needs to be programmed in.
The TDM is part #6.
PROGRAMMING IMMOBILIZER SYSTEM COMPONENTS
10-MINUTE IMMOBILIZER RELEARN
This 10-minute relearn procedure will relearn the prerelease password and the challenge/response data between the theft deterrent module (TDM) and the engine control module (ECM).
1. Connect a scan tool to the vehicle.
2. Turn ON the ignition, with the engine OFF.
3. Ensure that all power consuming devices are turned OFF on the vehicle.
4. With a scan tool, select Request Info. Under Service Programming System and follow the scan tool on-screen instructions.
5. Disconnect the scan tool from the vehicle and connect the scan tool to a Techline Terminal with the current Service Programming System (SPS) software.
6. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions. Ensure the correct programming selection is chose based on component being replaced or programmed. For this procedure, go to the V.T.D. Vehicle Theft Deterrent Learn menu and choose the Vehicle Theft Deterrent Learn, ECM, or PK3 Replaced selection.
7. Disconnect the scan tool from the Techline Terminal and reconnect the scan tool to the vehicle.
8. With a master vehicle key, turn ON the ignition with the engine OFF.
9. With a scan tool, select Program ECU under Service Programming System.
10. At this point the scan tool must remain connected for the duration of the 10-minute relearn procedure.
- The scan tool will initially display 12 Minutes. The first 2 minutes allow the scan tool to initialize the appropriate control module. The remaining 10 minutes is the relearn timer.
- On some vehicles the security indicator may be illuminated for the duration of the 10-minute relearn procedure.
Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to CRANK.
12. Turn OFF the ignition and wait 2 minutes.
13. With a master vehicle key, turn the ignition to the RUN position for 15 seconds, then start the vehicle. The TDM and ECM have now relearned the pre-release password and the challenge/response data.
14. With a scan tool, clear any DTCs.
Images (Click to enlarge)
Tuesday, December 10th, 2019 AT 9:53 PM