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73-87 Chevy _ GMC Trucks => Electrical => Topic started by: Sodium Duck on March 18, 2012, 08:38:13 pm

Title: 3 wires on transfer case shifter...
Post by: Sodium Duck on March 18, 2012, 08:38:13 pm
White, black, and greyish. Which is 12 volt and ground?

No, I don't know how to use a volt meter...   :(
Title: Re: 3 wires on transfer case shifter...
Post by: Irish_Alley on March 19, 2012, 03:03:51 am
use your tongue. wish i could help but i have only messed with 2 wires my guess would be black is ground white is hot and gray is a signal for the dash cluster light
Title: Re: 3 wires on transfer case shifter...
Post by: bake74 on March 19, 2012, 09:00:31 am
use your tongue. wish i could help but i have only messed with 2 wires my guess would be black is ground white is hot and gray is a signal for the dash cluster light

     My bet is black is power, white is common, and greyish is the dash light for 4x4.  Do you know how to use a test light ?  If not you can make a very simple one at home. 
     Take a nail, get some 12 gage wire and a automotive light (single element like a blinker light), solder a end of wire to tip of nail, cut the wire in the middle or somewhere and solder the two ends of the wire to the light, then get a aligater clip and solder the other end of the wire to it (to use for a ground so you don't have to hold it).
      To test, clip the aligater clip to a ground source, use the end of the nail to poke the end of the wire you want to test, if it is a power wire the light will light up, if it is a ground wire it will not.  The dash 4x4 light wire I believe has to be activated by the power wire and transfer case wire, so it should not light up either.
     Check this and report back.  You should check out u-tube on using volt meters, it is not that hard and will be a great skill to know how to use one in the future.
Title: Re: 3 wires on transfer case shifter...
Post by: Irish_Alley on March 20, 2012, 12:23:08 am
why would black be hot when off the battery its ground and hot is red?
Title: Re: 3 wires on transfer case shifter...
Post by: bake74 on March 20, 2012, 07:00:20 am
why would black be hot when off the battery its ground and hot is red?

     It doesn't sound like the color wires are stock, if someone added them my guess would be they stuck to black hot, white common, though as I said it is only my guess.
Title: Re: 3 wires on transfer case shifter...
Post by: VileZambonie on March 20, 2012, 08:11:33 am
Why would you make assumptions based on wire color? It's irrelevant and most battery cables are black for both positive and negative. Look at the wiring diagram. Grey is B+ to the 4wd shifter light, Black is ground, The black splits to the 4wd shifter switch, white goes from the shifter switch to the 4wd relay to energize the 4wd indicator lamp.
Title: Re: 3 wires on transfer case shifter...
Post by: bake74 on March 20, 2012, 07:11:49 pm
      So I am going to make sure I read that diagram right, the black is the ground.  The white is actually completes the circuit through the 4wd indicator light, through the 4wd relay, and when the transfer case is shifted into 4wd complete's the circuit to the black wire for ground ?
     Did this come from the tech section or something you found Vile ?
Title: Re: 3 wires on transfer case shifter...
Post by: VileZambonie on March 20, 2012, 08:03:19 pm
I'm sure it's in the tech section but I pulled it out of my database.

The 4wd shifter indicator lamp illuminates when the park lamps are on. The 4wd indicator lamp in the gauge cluster illuminates when the switch completes the path to ground and the ignition switch is turned on.
Title: Re: 3 wires on transfer case shifter...
Post by: Irish_Alley on March 21, 2012, 02:12:02 am
vile this is where a test comes into play lol i wouldnt dare test the wires by color but if i had to i would lean to what kind of makes sense. normally i wouldnt try to guess but i saw no one answered so i tried to help out a brother 8) tell you the truth i was thinking there shouldnt be a hot since thats not what on mine but i only had 2 wires i dont know what i was thinking
Title: Re: 3 wires on transfer case shifter...
Post by: VileZambonie on March 21, 2012, 12:55:16 pm
I'm not picking on you just making a point, randomly testing wires is never a good idea based on assumptions. Always try to take a look at the schematic when possible.
Title: Re: 3 wires on transfer case shifter...
Post by: Irish_Alley on March 21, 2012, 06:36:16 pm
i know your not, just like when i posted i was just addressing your response. yeah a random test will only cause more problems when you ground a power wire lol. thats one problem with a online form you cant never tell how someone is talking to you
Title: Re: 3 wires on transfer case shifter...
Post by: Sodium Duck on March 22, 2012, 07:47:27 pm
Works great. Now my temp gauge lights up all pretty. Yay!