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Congrats Fern! pimp! definitely a small mod that makes a big difference! Where did you splice in to the lock/unlock wire?
 

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Discussion Starter · #23 · (Edited)
here is a quick DIY :)

here is how to hook up a SPDT relay to activate your mirrors. i used my door locks as the trigger. the trigger will be something which will go from 0v to 12V when you lock or unlock your car. this trigger will be used to fold up or fold down your mirrors. this DIY is intended to help guide you. i dont take any responsibilty if your car goes Kaboom. :thumbsup: please read it, understand it and ask any questions if your confused. now lets begin.

1) remove your dirver side door panel. tap into the door lock connector wire loom on the driver side door. this wire loom runs directly in the middle of the door right under the black foam cover. the wire loom has 10wires. you only need 2 of these wires as triggers. white wire is trigger for door lock. blue wire is trigger for door unlock. tap into these wires and then double check with a volt meter. verify that each wires goes from 0V to 12V as you lock or unlock the doors. white wires goes from 0v to 12v and back to 0v when doors are locked. blue wires goes from 0v to 2v and back to 0v when doors are unlocked.


2) now lets put some protection diodes inline with each trigger wire. these are required because each trigger wire will actually be going to one relay input. so.. when one is at 12V the other will be at 0V. to isolate these, a diode is used. just make sure that the cathod side is the side thats closest to the relay. the anode side connects dirrectly to your trigger wires. these diodes only allow current flow in one direction.




3) here is what a SPDT relay looks like from the back.



4) you can wire your SPDT like this.
pin 85 - trigger from door lock (white wire, blue wire. both with isolation diodes)
pin 86 - ground
pin 30 - goes to pin 2 on your auto fold mirror switch (0v from car which is ground and can be connected with pin 86 of relay)
pin 87 - goes to pin 4 on your auto fold mirror switch (5v from car)
pin 87a - this pin is not used. its the position the relay stays in when not in use (not energized)


5) when the relay is OFF (pin 85 is 0v when off), pin 87a contacts with pin 30. pin 87a is normally closed with pin 30.

Relay OFF



6) when the relay is ON(pin 85 is 12v when on), pin 87 contacts with pin 30. this will close pin2 and pin4 of the euro switch closed.

Relay ON



7) pics of the euro mirror switch




8) when your door locks or unlocks (pin 85 will go to 12v for 1sec and then back to 0v), the trigger will go to 12V and energize the coil and close the relay. this will close the circuit to make pin 87 contact with pin 30. in effect, this will short pin 2 and pin 4 of your auto fold mirror switch.



so basicly.. your using the SPDT relay to short pins 2 and 4 of your euro mirror switch. these only will short together when the trigger goes to 12v on pin 85 on the SPDT relay. note that the trigger which you use on pin 85 should only go to 12v and then returns to 0v. it does that every time you lock your car. it does it again when you unlock your car. if pin 85 is held constant to 12v, it only moves the relay to the other position once each time you lock or unlock your car. so.. that means that the mirror will fold up when you lock and fold down when you unlock. the important thing is to find the proper 12v during the lock mode and also during the unlock mode. also, it may be wise to put some type of protection diode on pin 85 for each trigger. if both triggers are used on pin 85, if one goes to 12v the other will be at 0v.. so yes.. an isolation diode is a must.
 

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Nice Fern! I gotta check this out... you da Man!
 

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dang, that's pretty cool.
nice!!! :bow:
 
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