SC- 1st Gen (1992-2000)

A/F guage wiring

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Old 07-25-02, 11:50 AM
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awj
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Default A/F guage wiring

I'm wiring an a/f guage from autometer that came with the car from the prev. owner. The thing never was wired correctly and I have since pulled it when I attempted to cerrect the wiring I found no good ground, power, or signal. The afc is hooked up so I figure I can tap off of the connections from it - the power, find a ground, and use the 02 sensor input to the afc also. Just a matter of pulling the carpet and locating the wires I guess.

Another issue is the damn electric fans. They have melted the switch that old boy put in there originally. I replaced the switch but now, I do not leave them running. Right now, I only turn them on in traffic if it is really hot or if I see the temps moving up on me. So far, she has held up. But I do not think there is a relay in there protecting the circuit - the wires get damn hot after about two minutes. It is a miracle the stuff has not burned out already. Flexalite makes a thermostat switch, manual switch and relay that I am going to order. But in the meantime, I was wondering on how hard it would be to wire in a relay on the circuit to keep these wires from burning up. I'm not very strong on the electrical stuff - depending on your all's input, I may try it myself or I will take it over to the car audio shop and see if they can wire me out of this crap.

I hate hack jobs. I don't even want to go into the stereo. That crap is coming out once she is prepped for paint and turbo.

Last edited by awj; 07-25-02 at 11:50 AM.
Old 07-25-02, 02:32 PM
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SC300T
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I pulled my O2 signal straight from the 02 sensor. The stock sensor wire (at the 02 sensor itself) looks like a single conductor, but in actuality is a coaxial wire. This tripped me up, cause I just soldered the wire and in turn grounded the 02 signal. This caused the meter to not read any 02 signal.

You have two main 02 sensors, though. I'd just tap into one of them and make sure that you tap in to the center of the wire, backing the ground sheath away from the center. Examine it closely, you'll see what I mean. You should get a good signal then.

Of course, the alternative is to tap off the at the ECU connection, but isn't that where you're having problems?
Old 07-25-02, 05:36 PM
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awj
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Yea basically. The previous install had the signal and power coming off of some wire that I can only assume is coming off the ecu connection from the afc and the gorund on a cigarrete lighter that is not connected. But there was a switch wired in on the gauge - I don't really know why, but I need to get under the carpet and look. Got to make the time for that. Just got on a rant up there. Thanks, I'll check out the O2 sensor. I actually found that in a thread from a year ago, I think it was you (or wiz) who said that too.
Old 08-04-02, 03:51 PM
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awj
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So I got in there this weekend. Rewired a couple of things. Got my stereo and climate control working again, thanks directql! I pulled the cover on the ecu and found the apexi harness, some stereo wire spliced into a blue wire on the apexi which was I believe for the mass air signal? I removed all that, reconnected the blue wire the way it should be. Found the purple signal wire spliced in to the ecu O2 signal, used the signal line off the gauge and reconnected those. Ran the power for it off a 5 amp fuse extended from the junction box. Vioala! It all works! I am suprised at myself. So I took her for a spin, the car seems to run better? I think I fixed something that was interfering with the afc, but not sure. Might be nothing. The damn a/f gauge is all over the place though. Just like on the car I used to have with one. I take it this is normal with these type of gauges from the searches I have done on this board wich yeild some really good information. Anyways, how would I make some fine adjustments to the afc with this gauge all over the place? I would not be for sure that I am leaning the mix safely. Guess a chasis dyno is required. Now I need info on wiring these electric fans so that the switch doesn't melt. There is a 30 amp fuse in line that is melted to hell. Anyone know where I can get a schematic or some directions? I contacted flexalite, but no response as of yet. These are the dual 210 model. No thermostat or relay is being used as far as I can tell. Anyone with these fans have some advice. If I can not get the wiring strait, I am going to pull them. Thing is, they work fine. The wiring just gets hot as hell and I don't run them until I see the temp gauge rising when in traffic because I am afraid of setting something on fire. Oh well. I'm happy I got the other issue strait. Ready to fix the paint, install my tt brakes, drop it and turbo me baby!
Old 08-04-02, 05:02 PM
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awj:

cool avitar!!
Old 08-04-02, 05:23 PM
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Hey thanks Em.

Old school.

I was hoping the reply would include a schematic for the fans though.

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