Pav. Ok so when the button is pushed on any of the 12v lines does the voltage Change at all? Also ohm out the ground wire to make sure it has proper ground. The first thing between the latch trunk is a noise filter pics on my old thread I sent In my last post. Might try seeing the voltage on that too.
Beware that if you take the filter out you can put it in backwards and it won't work label it before you pluck it.
Just remember that on the latch connector you need to see something happen when the button is pushed either voltage appear or disappear can't remember which one just so you know the signal is getting there.
To rule the relay on the circuit board you should hear a click noise when the button is pushed close to the glove box. If you hear it then you know that part is good.
Also try to exercise the valet key latch a few times don't know if you used it recently maybe it hung up.
Hope this helps I'll search for the diagram since online TIS is gone!
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