'7427 PCM not receiving brake switch input

[Daveo91]

guess i remembered backwards, sorry. my 86 gmc Cruise has a switch with a vac hose, maybe yours is newer style?

No worries, the “normally open/closed nomenclature” is a bit confusing for a switch that in the normal state has the button pushed. I think my factory cruise system does use vacuum tho - the switch originally did have a vacuum line attached to it.it’s still under the dash, plugged.

I think the old square body trucks had vacuum cruise but the GMT400s switched to electric controls, at least my 88 is.

sounds about right. So there’s no vacuum at all on the GMT400 cruise system? Uses an electric control to open and hold the throttle? That’s the system I want to convert to but I have the stuff from a vortec truck.