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GM Vehicle - Passkey III – Transponder Ignition Key

Written by John Wells | Jan 23, 2017 5:00:00 AM
The Passkey III anti-theft system uses a transponder inside the head of the ignition key. The exciter inside the ignition lock cylinder energizes this transponder when the ignition switch is turned on. The transponder transmits a unique signature to the theft deterrent control module. If the key signature transmitted is acceptable to the theft deterrent control module, the theft deterrent control module will transmit fuel enable password to the PCM. If the "fuel enable" password is correct, the PCM will start the vehicle. Check out the relearn procedures below, and contact UpFix if you have any questions!

GM Vehicle Theft Deterrent (VTD) Relearn Procedures

To perform a relearn for Passkey III system, make sure there is a fully charged battery in the vehicle. The battery will be used for 30 minutes without the alternator available for charging. Connect a battery charger to the battery to ensure power is available while programming. When performing this relearn, all previously learned keys will be erased. Additional keys may be relearned immediately after the first key has been learned by inserting the additional key and turning the ignition switch to on within 10 seconds of removing the previously learned key.
  1. Insert a master key (black head) into the ignition switch.
  2. Turn key to the “ON” position without starting the engine. Security light should turn on and stay on.
  3. Wait for 10 minutes or until the security light turns off.
  4. Turn key to the “OFF” position for 5 seconds.
  5. Turn key to the “ON” position without starting the engine. Security light should turn on and stay on.
  6. Wait for 10 minutes or until the security light turns off.
  7. Turn key to the “OFF” position for 5 seconds.
  8. Turn key to the “ON” position without starting the engine. Security light should turn on and stay on.
  9. Wait for 10 minutes or until the security light turns off.
  10. Turn key to the “OFF” position. The key transponder information will be learned on the next start cycle.
  11. Start the vehicle. If the vehicle starts and runs normally, the relearn is complete. If additional keys need to be relearned:
  12. Turn the key to the “OFF” position.
  13. Insert the next key to be learned. Turn the key to the “ON” position within 10 seconds of removing the previously used key.
  14. Wait for security light to turn off. It should happen fairly quickly. You may not notice the lamp, as the transponder value will be learned immediately
  15. Repeat steps 12 through 14 for any additional keys.
This is just one of many how-to guides provided by the expert technicians at UpFix. If you have questions about repairs for your Electronic Auto Parts, check out our other blogs, Videos, or contact us today!