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Silas Cruse

4WD switch wiring help please with pics! 1991 Loyale

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1991 Loyale Wagon  4wd MT

So my 4wd switch has failed for the third time.  :banghead:


My local Junkyards, near Salem Oregon often have parts available. I want to try a different solution.

My plan to is to install a 3 way toggle in the dash as a replacement for the stick shift button.

And then choose an awesome replacement shift knob.

I have researched but not been able to find a diagram of this system.
I did find some 1988 Justy stuff but only the vacuum/mechanical, not the electrical.

Note: Direct vacuum to each diaphragm line does work and actuate the 4wd ,

I heard the clunk, and saw the green 4WD light on the dash.


I am looking for the wiring diagram.


I want to know this:

Switch wire   -3 - white , red, yellow

wire from firewall - 4 - blue, green/yellow, black, black (2) .

plug:plug to vacuum switches black black, white white.


vacuum switches 1 has 2 black , 1 has 2 white.





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You need a single pole Double throw without a center off.


Basically both solenoids get one wire to ground each.  doesn't really matter which, you could test for continuity to determine which wires are which, or start from scratch and run your own.


Then the 2 other wires, one or the other should get 12v+ at any given time.  


Check the wires inside for 12v+ with key on.  That is the supply, the other 2 are 12v+ out to either solenoid.

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