I'm trying to plan for my tranny temp gauge install, and figuring out how to wire to switched power and then how to wire to the headlight switch for the background light are giving me problems...

can anyone explain where or how this is done?

I'm looking at using one of these gauges...http://www.amazon.com/Auto-Meter-435...=vglnk-c565-20

 

I dont know newer rig's but on my 1992 i figured out what power wire sends a signal to the clock to dim when lights turn on and i went off that.

 

cig lighter or radio wire ?

 

fuse block under acess panel to the left below steering column.

 

I use a relay, switch the relay from some switched power under the dash (use a multi-meter to find one, the above are good suggestions). The relay then powers a fuse block in my case. Everything I wire in then hooks up to the fuse block.

 

The ignition wire is black and yellow in the ignition harness, pretty easy to access. remove the 10mm bolts holding in the plastic knee bolster under dash. then i think another 4 removes the metal guard and you can see your ignition harness.

i cant remember the color of the headlight wire off the top of my head, but there are only 3 wires, test the wires for voltage as you turn on the lights. you should get 12volts when you have regular lights on, as well as high beams. make sure you dont grab the wire for high beams, or the light will only illuminate with high beams. i believe you may even be able to tap it off the parking lights wire as well



this is all based off the truck in your sig, so im assuming its for a 97 runner

 

Ignition wires color is black/yellow as said above. If you go to the stereo or the cig lighter, you will get acc power. not what you want for your gauge, but i would work.

You dont need a relay for a gauge.

You do not need the headlight wire for the illumination of the gauge. You need the dash illumination wire of the truck. Toyota uses green wire for this and probably easiest accessed at the dimmer switch (the rotary know you turn to make the dash light more or less bright) on the left of the dash.

 

thx for all the responses

I think I have plenty of info to do the wiring myself now.

appreciate it, and I'll take some pics and let ya'll know how it went.

 

I have a Painless Cirkit boss fuse block with 4 relay switched circuits for various extra gauges I've got. The relay wire is tapped into the ECU's power wire, so my gauges only turn on when the ignition is in the <ON> position rather than <ACC>.

Just food for thought. The easiest wire to get to is probably the cig lighter, but it turns on in the <ACC> position.

 

I hear you...but I'm thinking acc power is fine for me. I dont have the truck sitting with the key turned to acc, so I'm thinking it doesnt really matter?

one thing I'm trying to determine is the best electrical connectors to use when tapping into another wire?
I remember I had a miata where they used a certain type of cheap wire splice when doing the alarm and it gave me electrical fits for years before we figured it out.

I dont want to run into that problem...

 

Your best bet is to cut back a .25" section of insulation on whichever wire you're tapping, solder your new wire on to it, and then heat shrink the joint. The wire tap connectors are convenient, but can give problems down the road.

 

Ok, that is what I needed to hear I guess, as I was just thinking the same thing
I have a solder gun and have done this before, so no problems there...even have some heat shrink tube.
I definitely dont want more problems down the road with electrical

thx

 

you arent really going to be able to shrink tube the wires unless you cut the main ignition wire in half at some point, otherwise you would not be able to get the tubing over the wire. the method i use is similar, but just use electrical tape. do not use scotch locks, t-taps etc. i have seen them fail and cause lots of issues.

get a pair of side strips from home depot, they make it very easy to strip the wire without risking snapping it.

then take a pick tool, or flat head screwdriver and carefully make a small hole in the exposed wire ( make sure not to touch any metal with the object you put through the wire, risking a short. just keep the ignition off )

once you have made the hole, take the wire you will be adding, and twist the exposed end, so it is a tight wire ( hope that makes sense ) then feed the new wire through the hole you made, and around the exposed wire, almost like threading a needle.

next solder your wire in place, and it doesnt hurt to support the new wire on the existing ignition wire using a zip tie. zip tie the two together just above the exposed wire, this is just an added step to prevent it snagging or coming loose from vibrations.

after you have soldered the wire and supported it with your zip tie, use some quality electrical tape (3m superr 33 ) and tape up your wires.


hope that made sense, if not i can try to take some pics and post them for you.

 

this link shows what i am trying to explain, all but the added zip tie part. go about 1/2 way down the page to where it says: "how to solder" that gives a pretty much step by step picture guide to what i just explained

http://www.mmxpress.com/technical/connections.htm

for the most part, i would just put a small zip tie right next to where the tape ends in the last picture right before it shows how to "butt connect"

 

Man, all that stripping, soldering and heat shrinking sounds like a ginormous PITA for a gauge. I haven't had my '98 long enough to have explored the fuse box, but shouldn't he be able to get all the power he needs there with a couple of these?:

http://www.amazon.com/Wirthco-30800-.../dp/B000CQDRTI

or these:

http://www.amazon.com/Bussmann-BP-HH.../dp/B000GKEXK2

They may not be the most bomb-proof, but it's an auxiliary gauge and these don't have the potential to introduce problems to other circuits by tapping into main wires that serve the whole truck.

Or what about a couple vampire taps on the cigarette lighter wires? I've personally found these to be totally reliable but apparently others haven't. OK, but what's the worst that could happen? The lighter and the tranny temp gauge stop working at the same time? They're just not that important and are dead-simple to troubleshoot.

Just seems like going after the main wires of the ignition switch and cutting them would be a lot more likely to cause headaches than a couple of vampire taps on the cigarette lighter or a couple of fuse taps. That's how I look at stuff like this, anyhow. I try to F with the factory wiring as little as possible, especially in vital areas. I can see it in the case of installing an auxiliary block that you're going to run a bunch of stuff off of, but this is a single gauge. Even if I was doing that though, I'd take power straight off the battery switched by a relay connected in nice and simply. Just a fundamental difference in philosophy, I s'pose.

Chris

 

Im just giving some suggestions on how to do it the most fail proof way in my opinion. fuse taps, t-taps all those "add on" accesories are just one more thing to fail in my opinion. its almost as easy to get to the ignition wires as it is to get to the cig lighter wires in these trucks. I know its just for a trans temp gauge, but again why take the "easy" way when the more secure way may only take a little extra time, if any.

I know you said its not a big deal to troubleshoot if the wire were to come loose, and its only a guage or a cig lighter, but why take a shortcut that may risk more work in the end? also would you want your trans temp gauge to fail and worst case scenario your trans overheats beacuse you wanted to take the easy way? i know i would not want to take that risk.

im not knocking what you are saying at all, just giving some feedback to your questions. i install professionally and have for many years, and have seen some pretty nasty results from people using those taps, or just taking a short cut in general, but then again those people have helped keep me busy with fixing their mistakes for many years

 

You could go to the fuse panel and use one of those adapters that has a spade on the end that seats below the fuse and just connect the wire to the spade