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ls1nova71 · 10-12-2017, 02:40 AM

You'll need a 4 prong brake light switch, the kind used for cruise control in the 70's and 80's. They have 2 sets of contacts, one normally open and one normally closed. The TAC ties into the cold side of the brake light wiring and the PCM side will be the other set that needs ignition power and will send power to the PCM when the brakes are not applied.

10-12-2017, 02:40 AM	#39
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,118	Re: DBW Cruise Issue You'll need a 4 prong brake light switch, the kind used for cruise control in the 70's and 80's. They have 2 sets of contacts, one normally open and one normally closed. The TAC ties into the cold side of the brake light wiring and the PCM side will be the other set that needs ignition power and will send power to the PCM when the brakes are not applied. __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html