4wd light

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Frank
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4wd light

Unread post by Frank »

Im trying to wire in a light on the dash to indicate front wheel drive. (twin sticked) The switch in the T-case has never been hooked up. There is another one that has a two pin plug for the reverse lights. This is a single pin plug that I assume has a detent ball to activate the light. I ran power through a dash light and down to that switch. I shifted to front wheel drive and no light. If I ground the light it works . Wouldnt the T-case switch make it go to ground so the light comes on ? Do you think the switch is bad or am I just missing something here ?? Help the retiree out. Thanks FjR68
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Kurt
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Re: 4wd light

Unread post by Kurt »

Frank,

It sound like you have it hooked up correctly and it should work.
I'd suspect the switch is bad.

You can try taking the switch out (I assume it screws into the tcase like most).
Leave the wire from the dash light connected to it.
Connect a jumper wire from the threads of the switch to ground.
Now actuate the plinger of the switch and see if the light goes on.
If it does then the plunger isn't being depressed enough when it's installed inthe tcase.
If the light doesn't come on then it would seem the switch is NG.
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ArticRubi
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Re: 4wd light

Unread post by ArticRubi »

Im not familiar with the electrical system, but I'll give you some thoughts...With just a single wire it sounds like it is a ground switch. Basically, there should be a constant 12V, possibly less if there's a voltage regulator in the instrument cluster, that is wired to the light. The wire to the transfer case is simply a ground wire for the light: when the transfer case engages 4wd, it establishes a ground for the light, thus lighting it up. Usually when the + side of the circuit is switched, it is done with two wires.
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Frank
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Re: 4wd light

Unread post by Frank »

Thank you both. Thats exactly how I thought it should work. When twin sticking the 300 you have to change one of the shift rods , Im going to check which one it was and if that eliminates the 4wd light or if its just a bad switch. I want to use it as a couple times in Rausch it had come out of 4wd and then I would have an issue climbing something and find its not in 4wd , just 2wd low range. The light will now tell me front wheel only or 4wd. You guys are the best. FjR68
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Frank
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Joined: Sun Dec 27, 2009 8:54 am
Jeep Year: 1974
Jeep Model: CJ5

Re: 4wd light

Unread post by Frank »

Taaa Daaa ! If the switch is screwed all the way in , it works just fine. No I can tell if it pops out of 4 wheel or front only. Thanks guys. Cant wait to wheel ! FjR68
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Kurt
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Re: 4wd light

Unread post by Kurt »

Excellent! :banana-guitar:
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