I have read most of the write ups and diagrams. But would like to know if on a 93 Z would this mod cause a check engine light?
1) Would just tapping into the temp switch at the pump and running that into a switch to activate a ground work?
2) Use the pressure switch on the AC line, is this a way to activate?
3) Or just hot wire 12v to the fan motors?

At last the write up for the OBD-1 by wiring the 2 fan wires together and then activate a ground via a switch the more common way? Check engine light with this?

I have done this on a few of my cars in the past, I just ran a wire from the relay that was grounded by a switch. Will this set off a light?

 

1 or 2 would not work and 3 is a poor and unsafe way to do it, IMHO. Instructions are on my site to safely run them with the stock relays and cause no check engine light. Just substitute LH fan for low speed and RH fan for high speed as designated on the schematic. It will still work on the early two relay fan system.

 

Thanks for a reply and your time. Your information on your site I have found very helpful on a number of things.
The question that I have is that on my 93, I dont have the 2 connectors that you show on the fender well.. Only one cluster of wires joining together. I dont see any blue wires. Is there a different color?

 

C100 (I know you don't have C105) should have a blue and green wire in cavities H and J just like all other years.

 

No.You have other issues.Get the car scanned . most likely a cat prob.Or third light thing.my02.

 

I dont have a light on. I just didnt want a light on because of a fan mod! Thanks Shoe....

 

I did my fan switch today, made a nice control panel with LED lights, but I have to buy some diodes for the wires coming from the fans. The LED lights are on when switch is off.....
where do you guys buy these? 1-3 amp diodes?

 

If you change it to a power source that is only on when the key is on, you won't need diodes. Radio Shack should have the diodes, if you need them.

 

Thanks, I think I will just rather hook it up with a switched power. Thanks again Shoe...

 

Shoe, where is the best location to tap into a switched power?

 

Look in your dash fuse panel and see if you have a spare terminal that is marked IGN. That should work.

 

Hey guys new to the site here. Why not just get a manual fan switch from SLP? Thats what I did on a couple of the different F body's I've owned works like a charm with no side effects.

 

I did it how Shoebox discribed on his write up. I did tap into the IGN location, ran the wires from the fans through the firewall below the computer on the PS. Made a control panel and used 2 LED lights for low (orange) fan and high (red) fan using a DPDT switch. That opening where the CD's go that I never used is where I made the panel. Looks clean, and now I can run the fans when I want to. That is the whole idea.
Thanks Shoe for all your help. made things easy!

 

93 doesn't have "low" and "high" fans. It has "fan 1" and "fan 2". The change from fan 1/fan 2 to both fans low/both fans high was made in the middle of the 94 model year.

The fan actuation signals from the ECM (93) use the same wire colors as the later years, with low/high, but the function is different.

 

Which mean Low is the #1 fan on the bottom driver side and High is both fans with the #2 fan being top fan passenger side. I believe.