GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 35628-A PASS/VATS Interrogator

In order to replace lost ignition keys it is necessary to determine the mechanical cut and the electrical key code.

The mechanical and electrical key codes are recorded on the vehicle invoice. Use the codes to create a new ignition key, if available.

Determine the mechanical cut first. Use the key code on the ignition cylinder or call Divisional Roadside Assistance in order to determine the mechanical cut.

If the mechanical cut cannot be determined, replace the ignition cylinder. Make an ignition key blank with the correct mechanical cut. Use the blank key while determining the proper electrical key code.

Complete the following steps in order to determine the correct electrical key code:

Important: Do not disconnect the yellow two-way SIR connector.

  1. Connect the J 35628-A wiring to PASS-Key II® connector at the base of the steering column. Do not connect to the steering column wiring.
  2. Turn the J 35628-A ON and position the key code switch to number 1.
  3. Attempt to start the engine with the proper mechanically cut key.

    If the engine starts, the key code is number 1.

  4. If the engine does not start, turn the ignition OFF and press the 4-minute timer on J 35628-A .
  5. When the timer lamp goes out, move the key code switch to number 2 and attempt to start the engine.
  6. If the engine starts, the key code is number 2.

  7. Continue trying different key codes until the correct key code is found.
  8. Make a new ignition key with the proper key code and mechanical cut.