My 87 Fiero with a 3800 series II SC has two brake switches.

I have eliminated all but one connector by reading various threads here, (see below)

Switch #2
Connector - with Yellow and Yellow and black stripe - I haven't been able to figure out what this controls???
Connector - with Purple and Pink/Blk Stripe - TCC

Switch #1
Connector - with Lt Blue, Orange and White wires - Brake Lights
Blue Connector - Cruise control

Anyone have any ideas?

Thanks
SM

The unknown wire may go to the ECM. 3800 series engines have a DFCO(deceleration fuel cut-off) function wired through a brake switch.

quote Originally posted by AsaBergman: The unknown wire may go to the ECM. 3800 series engines have a DFCO(deceleration fuel cut-off) function wired through a brake switch.

Thanks Asa, I'm not sure either, but I will fix the mounting and keep it in place.

The yellow and yellow/black wires are part of the cruise control circuit.
When the pedal is depressed, the circuit opens and removes power from the coil in the Vacuum Release Solenoid.

There is no DFCO circuit used in a 3800 swap in a Fiero.

quote Originally posted by olejoedad: The yellow and yellow/black wires are part of the cruise control circuit. When the pedal is depressed, the circuit opens and removes power from the coil in the Vacuum Release Solenoid. There is no DFCO circuit used in a 3800 swap in a Fiero.

Thank you for the input olejoedad!

I thought the Blue plug (with the two wires grey and Brown/White) was the cruise control?

what is that connector for?

There is actually more than one switch associated with the cruise control operation. The switch with the gray and gray/white wires is the "brake switch". The output goes to the cruise control module.

The other switch with the yellow and yellow/black wires is the "cruise brake switch". It's output controls the "cruise release solenoid".

I assumed you have an automatic as you commented about the TCC.

If you have a manual the are 3 switches.

[This message has been edited by Cajun (edited 09-19-2018).]

quote Originally posted by Cajun: There is actually more than one switch associated with the cruise control operation. The switch with the gray and gray/white wires is the "brake switch". The output goes to the cruise control module. The other switch with the yellow and yellow/black wires is the "cruise brake switch". It's output controls the "cruise release solenoid". I assumed you have an automatic as you commented about the TCC. If you have a manual the are 3 switches.

Thank you Cajun!! Good info, much appreciated!

Yes an Auto trans

Car currently does not have cruise. Will do a little research to see what I need to run the digital system with the 98 3800 Series II SC

Digital cruise is not hard to install, check gmtuners.com for instructions.