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Switches and Relays

As my back grew tired from leaning over the fender well to work on the relays, I decided it was time to go back into the cab and do some more work on the console wiring harness.  I still had to put some of the vehicle side wiring together to mate up with the console connectors.



This some some of the "before" wiring that had slowly accumulated under the dash and with it is some of the new relay rack control wiring.  What a mess! 

I went through my "wire junk box" where I keep my odds and ends of electrical wire, connectors, switches, fuse holders, etc. to see if I had something suitable for the relay control wires.  I found a multi-conductor cable comprised of six 18 gauge insulated wires.  Since I had room for six relays on the mounting bar, I decided to route this cable through the firewall and hook it up to a 12 pin Molex connector.  This would match up with the group of switches that were mounted on the center console. 



I soldered the pins onto the end of the relay control wires and inserted them into the 12 pin Molex connector.  On another six pins, I attached +12V switched ignition power.  So each pair of contacts would then be attached to a pair of switch contacts.  When the switch was closed, it would apply +12V to the corresponding relay coil and energize it.  Things cleaned up nicely with some wire loom and a few more zip ties.  I was down to putting the console back into the TJ.


The Molex connectors were plugged in and the console was wired and ready.  I 'll get under the dash one more time and tidy up the cables a bit more when I get some time.  It was nice to install the dash and just plug the connector together. 



Another addition to the center console was an orange LED indicator.  I mounted it adjacent to the tranny temp gauge.  When illuminated, it lets me know that there is power to the 12V fan on my tranny cooler.  I can usually hear the fan (out on the trail) but if I don't hear it, and the light is on, I probably have something wrong with the fan and I'm not getting the cooling I would be expecting.



Still not done with the last of the relays, but it is getting closer.  Once I am finished mounting them, I'll zip tie the wiring back and straighten it up a bit.  To cut down on the amount of wiring required, I connected one end of each relay's coil (the blue wire for these relay sockets) to ground.  I crimped a ring terminal onto the wire and put it under the #10 screw that holds the relay in place. 

That about does it.   This is one way to install a bank of relays and the necessary switches for your electrical projects.  It will hopefully give you some place to start and provide you with an idea or two on how you may want to do yours.  Remember to always fuse your circuits.  It is the best way to prevent electrical fires. 

Enjoy your Jeep and remember to TREADLightly! 




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