Steering Column Repair: Pass Lock System...missing chip


Question
QUESTION: Make: GMC  2000 Sierra...Problem: missing  pass lock Chip..

Had to replace the original ignition lock housing due to it being deflective.. The original housing had/has a pass key chip mounted  with a 3 wire connector..

The problem come into play n that the replacement housing does not seem to have a chip but what appears to be brass cover where one would go. After installing and attempting to crank it with the 3 wire connector loose, it crank momentarily before shutting down and the security light comes on and does not blink..

What would be a procedure to connect the original wires together and not have to replace the Housing and than run the relearn procedure??  The new (used) housing came with original keys but did not use it because I bought a new tumbler and keys that I want to use,,, I can try the cylinder that came with substitute housing but that still leaves the question as to what to with the original 3 wire connector..

What would be your solution this problem...??

A second problem is reconnecting  a black cable into the ignition housing..what is that cable's function and how is it reconnected...

Sure hope you can help with these 2 problems..

Bobby Cook


ANSWER: Hi Bobby:

Sorry about your truck.  The lock housings cannot be interchanged.  If you have passlock, then you need a passlock housing.  Once installed and relearned you can then bypass the system, but the truck is looking for the sensor to be activated before it will allow you to start. (Sorry)  It's not like the old VATS system where you can put in a shunt or a bypass.  The sensor inside the housing is looking for the small magnet on the original lock cylinder.  When you start your truck, that magnet passes by the sensor and tells the BCM that the correct key is being used, not a screwdriver.  then it allows the fuel pump to continue to run and the ignition circuit to remain completed.
The black cable is your shifter interlock.  That cable is installed into the new housing when you turn the key to the ACC position (all the way back).  It prevents you (or a child) from shifting the truck until the key is turned to the run position.

I hope this helps you resolve your issues.
Good luck

---------- FOLLOW-UP ----------

QUESTION: Thanks very much for the info on the shiftier cable!!!!!!!!That really got me going..!!!

As for the no crank ..my bad..it turns out I was overlooking it on the housing..It is indeed a pass lock housing.. It is all together now..

I tried the relearn procedure with the new cylinder...After 10 min, as you said the Security like stopped blinking, went out and the battery light came on.  It still would not  start from the on  position \...It sputters and shuts down..How many trips would it take the for leaning process to work? I ask this because it seems every time I tried it, more dash lights came on.

Would it be OK I swap the original cylinder back in??


Thanks for your patience and help.

Answer
Hello again Bobby:

It takes 3 successful consecutive cycles of the 10 minute learn process (without trying to start it between each cycle).  I have had to do is as many as 6 times on stubborn vehicles.
Yes, you can use the original lock as long as the small magnet is intact.

That should do it.