This thread has been covered so, I did all the hardware swap. In the OEM harness the green connector in fuse box bottom the manufacturer added a extra purple wire to supply current to button to collapse relay, I had to take the the Jimmy bcm and figured out you can trick the module by unplugging your old bcm w blazer running and this automatically makes where the truck will restart so then you can use a key encoder to finish oh bonus I used the tricked module and found wifey has security now so need to get fob.🤦 job took 2.5 hrs all said and done as I had to repair a bad connection on drivers side signal.

 

Deleted

 

What wiring goes to the fog light switch

 

Year and model?

George