Hi
Rather then follow different threads, can someone point out where the fan relays are specific to model years...specific to my 1989 Formula, for example

I'm a novice on my car's technical layout and can't get a Helm/GM manual at the moment. I'm looking to ground the relay for fans on with the key in, although if the relay is an issue/at fault, will that still work? Can I add an on/off manual switch into the circuit already, or does it need to be changed as seems to be described in the various threads? I really need some visual pointers being the 'dummy' I am, most of these wires are hidden in the corrogated tubing insulation on mine

Bill

 

This is a scan from the factory helm manual for an 89 firebird. Sorry it's not a pic, but I think the diagram is pretty conclusive. I hope it helps.

If you want to add in an on/off switch, the easiest way to do it would be to splice into the ac pressure switch. If you ground that connection with the engine running, it will activate BOTH fans.

 

I don't have a good idea about how EXACTLY to do that, can you give a bit more step-by-step so I don't muck it up? I'm slightly competent...hehe
I recently removed the tire and under pass wheel well protectors to get the old antenna unhooked...that was VERY tough and it's still stuck in there, unlike my Cadillac the space is minimal to say the least, as is the engine bay....working from the top

Thanks!
Bill

 

I figure I found the location of the items, that was a tremendous help, but took some effort to get saved for printing on my lame-duck PC. Anyway, If I tap at the A/C switch to ground, which wire is that? I have some Radio Shack alligator/test style clips I could easily remove as well, if there's a problem, like battery drain. I'm looking to mod ASAP, so please give a quick response on this, thanks again, sorry for the DP
Bill

 

There should be 2 wires going to the pressure switch. One of them should be gray. That is the one to ground. When that wire is grounded, it will activate the secondary fan when the key is on, and it will cause the ecm to activate the primary fan when the key is on and the engine is running. If you want to test it first, all you have to do is unplug the connector and ground it with a paperclip.

 

Thanks, I hope the Radio Shack cord will function properly.... I like the micro terminal it has, as I don't have to remove much tubing/insulation, etc, and it clamps good (sliding connect covers bare metal). I found these nice to bypass bad home electronic terminals as well.
Bill

 

Looking at them, it seemed they were white and black, w/o checking again.
While the terminal was unplugged I tried grounding both at a time and restarting the ignition....nothing. Fans are inoperable still
I've heard there may be a fuse under the kickpanel? Do you know about that? Or are the relays faulty and causing it not to work this route?

Bill

 

Just looked at the classic HPP of December 1997, as it happens.
There was a cooling question regarding a 1989 TPI 350, in closing, the main suggestions echoed here, it was also advised that the grounds be tied together for both relays to activate together. Wanted to get your guys take on this.

I tied the main green/white wire I assume is the ground to close to the chassis mount of the aux relay with no fans still... What do I do next? Replace a block sensor?

Bill