rotarynemesis

Well I got my car back today finally after being down for about 6 months and I noticed my temps were higher than usual so I quickly pulled over and popped the hood. To my surprise the radiator fans werent on so I figure this is my problem. I looked through the fsm and tested the fan motors like it says so its not that. What could be causing this?

Mahjik

iTrader: (1)

Have you checked the relays?

rotarynemesis

There is a relay named cooling fan and its a 30A relay I think and I swaped it with some of the others and nothing happened.

Is there a relay for it in the front box by the hood latch because mine doesnt have a sticker on top of it.

Kento

That's not the relay, that's the fuse box. The four relays are positioned on the passenger side just behind the headlight. There is a group of four on a metal bracket; these control your cooling fan functions. Check your FSM for details.

rotarynemesis

Ok yeah I forgot about those. What would cause them to go bad?

Does anyone have a picture of the sticker ontop of the front box?

rotarynemesis

Checked all 4 fan relays and they look brand new. I cleaned the connectors and then hooked it all back up. But the fans still arent coming on. Is there another way for me to see if they are working.

Mahjik

iTrader: (1)

If you run power straight to the fans (around the relays) and the fans work, then the problem is with the relays (or the thermoswitch depending on what ECU you are using).

mad_7tist

do they come on when you turn on the ac? that will help you as you can eliminate a relay and swap for a known good one. if they still dont work you may have a bad themoswitch like mahjic suggested

rotarynemesis

No A/C

rotarynemesis

Is there a way I can wire them to a switch so I can just manualy turn them on?

Mazda99Nikon

Two things you might try temporarily.

1. Someone mentioned in another thread that if you have a 93, you can pull the connecting wire from your rear glass de-icer. When you turn on the switch on your console, (at least for this fellow) the fans will engage. I haven't tried it on my 94 yet, but it sounded like an interesting idea for the summer.

2. There are some occassions when my fans don't come on either. I don't have a thermostat gauge yet, so I'm not sure if there is a problem, as it's been a very cool summer in central Illinois, but if I turn off my engine when I park my car and then turn the car onto acc setting with the ignitition, the fans will engage. If I've been running the car really hard, they will stay on for around five to seven minutes. They have come on by themselves on a couple of occassions, so the system must be working, but I suspect there is a fine line there where something isn't calling them to be activated unless the engine is getting hot. I have a downpipe and my under hood temps stay really pretty cool compared to my 2Gen. You might give it a try until you can swap out those relays.

rotarynemesis

In that pic from the fsm it says the top one goes to positive and the bottom one goes to negative.

When I do that the fan comes on so that means the motors work. So can I just ground the bottom one and wire the top one to one side of a switch and the other side of the switch to the battery.

Will that work?

Kento

You will need the relays, otherwise it will create a nasty arc from the current draw every time you flip the switch, and the switch will soon weld itself together (or possibly start an electrical fire), and also because the wiring through the relays determines what speed your fans will run at. If I'm not mistaken, that test diagram only runs the fans on low speed.

TwinTriangles

Do the "Fan Mod" first...
Then check your relays, looking at them wont tell you anything, I've burnt mine out a few times because the get wet somehow, Now I just buy some regular relays from Checker for $4 instead of paying $30 for one new one at mazda...

rotarynemesis

does the fan mod work with the PFC because I tried it and it didnt work.
How do you test the relays?

Edit: I was told that if I unplug a sensor or something from the back of the coolant filler neck that the fans will come on the whole time the car is on.

Anyone know if this is true or have anymore info on it.

rotarynemesis

Ok so to test the relay like it says in the fsm I can just connect a wire to each terminal of the battery and connect it to two terminals on the relay and then check for the same current on the other two terminals with an ammeter?

And if there is no current then its a bad relay right.

skotx

Try this:

Look for the diagnostic box on the driver's side of the engine bay. Get a peice of wire and stick it in the terminal labeled TFA, and then touch the other end to ground. This should cause your fans to come on low. If this works, run a wire from the box to a switch inside the cabin, wiring the other side of the switch to ground. Just don't forget to turn off the switch when you leave the car, or you'll kill your battery.

This should be good enough to allow you to drive the car, but you should still track down the real problem.

-Scott

rotarynemesis

^ Well I put it in the TFA slot and wired it to a switch with the other end on a ground and it didnt work. But when I start the car they come on when the switch is on. So your method works but on my car when its shut off the fans go off also.

TwinTriangles

Yes, The fan mod will work fine with your PowerFC, I would have never made it this far without doing the fan mod, I just monitor the Temps on my Commander and if I start to heat up more than I like I flip a switch and 2 minutes later it drops straight down to 83c...