Headlight still goes up while disconnected? (Page 1/1)
Additivewalnut APR 04, 02:08 PM
Not a very important thing here, just curious on how this works. My passenger headlight motor limit switch died and I'm currently getting ready to do a gen 2 swap. When I put my headlight down it spins forever, therefore I have the blue single wire disconnected; but with that disconnected, the headlight will still go up, but not down! I'm not really sure I understand how that works? Is there an entirely separate circuit for going up?
1985 Fiero GT APR 04, 02:12 PM

quote
Originally posted by Additivewalnut:

Not a very important thing here, just curious on how this works. My passenger headlight motor limit switch died and I'm currently getting ready to do a gen 2 swap. When I put my headlight down it spins forever, therefore I have the blue single wire disconnected; but with that disconnected, the headlight will still go up, but not down! I'm not really sure I understand how that works? Is there an entirely separate circuit for going up?



Yes that's how it works, the blue is v+ for going down, the 2 wires going from the relay to the motor directly are v+ up (which acts as a ground for v+ down, and has the circuit breaker) and a ground (only used for up) that way the circuit breaker is always used, it ends up on the ground connection for down, and the +12v side for up.

[This message has been edited by 1985 Fiero GT (edited 04-04-2024).]

1985 Fiero GT APR 04, 02:15 PM


The limit switches in the motors are the outer most boxes, then the relay connects with 2 wires, with the 3rd (blue) wire having its own seperate connector going to the isolation relay
Additivewalnut APR 04, 02:52 PM

quote
Originally posted by 1985 Fiero GT:

The limit switches in the motors are the outer most boxes, then the relay connects with 2 wires, with the 3rd (blue) wire having its own seperate connector going to the isolation relay



That feels so needlessly complicated
1985 Fiero GT APR 04, 08:41 PM

quote
Originally posted by Additivewalnut:


That feels so needlessly complicated



It is definitely complicated, but for a reason, they needed to design a purely electromechanical system that was (supposed to be) reliable, while not catching on fire if one or both motors, or a relay, or anything really, failed, that connection in the blue wire is for peace of mind, for people working under the headlights, so they pull it and the lights can't go down and crush their hands. It is really complex, which makes it hard to work on later, I finished a system for winky headlights using the gen 1, without changing the factory wiring or the way the factory headlight switch operates, it was quite complicated getting through all those wiring diagrams!
buddycraigg APR 12, 12:52 AM

quote
Originally posted by Additivewalnut:
That feels so needlessly complicated


A long time ago, someone called it a ballet of mechanics and electricity (or something like that)
I thought it described it well.