deruvian

In short, my FAL fans keep blowing their fuse. For more details, please read on. I could really use some advice on this one.

So my FAL fans have been on the car for a little over a year, and for the most part they are great.

Not too long after I got them, the mini 30amp fuse that came with the kit blew. I figured it was either a faulty fuse or faulty inline fuse holder. I replaced both, and all was well for a good while.

A couple months ago, the fuse blew again. I replaced it, and it blew (intermittently) a couple more times. Frustrated, I bought a new relay, fullsize inline fuse holder, 10 gauge wire for the power and ground, and 14 gauge for the control. I installed it all, checking it with my multimeter as I went. I cleaned a new ground, and the continuity check was great.

The fuse is still blowing intermittently.

I have a year-old Optima yellow top, rebuilt 120amp alternator, and a new Koyo race radiator. What could be the problem?!

Thanks everyone!

evileagle

how exactly are you wiring them? Are you running the power directly from the battery or are you using a relay?

TJohnson

Since you talked about having a relay, I will assume you ahve it wired directly to the battery via a relay.

What are you using for the 12v ignition source? Are you going back to the fuse box there too or are you splicing in somewhere else under the engine bay?

Are they being thermostatically controlled as well? Or are they on all the time?

It sounds to me like something is getting a surge or providing a surge somewhere that is blowing it. If the fans are temp or thermo controlled, that could be why. If they shut off and on too many times, and the circuit that its tapped into isn't capable of handling that, then it could fry the fuse.

Just a place to start anyway. I've had my fair share of problems w/ elec fans in the past myself.

qksl2

I always use two relay's with those fans. Also, don't use the mini fuses. 30a should be fine.

Ian

TLDriver

iTrader: (4)

check how much amp's they are constantly pulling and if happens to be around 20-25 amps then maybe when they spike it might causing them to pop. If that is the case a small cap will fix that issue.

deruvian

Yes, it's hooked up to the battery directly. The 12v switch is just a fuse tap on one of the fuses in the interior (fuse panel near the clutch pedal).

There is no thermostat. I thought that the controller that came with the kit may have been the culprit, so I ditched it and just went with a relay.

I made a little diagram real fast - this should answer everyone's questions about wiring:

deruvian

Yeah I'm not a fan of the mini fuses either.

How (and why) do you use two relays?

Oh boy, time to go buy an amp clamp meter (my multimeter only handles 10 amps).

A cap seems a little overkill, as so many cars have electric fans from the factory. Anyone else have any ideas?

qksl2

One relay per fan. You can individually control them on a switch, but I like to use a thermistor to control the fans. These are pretty cheap from Summit or Jegs.

Ian

deruvian

Gotcha. And what amperage fuse do you use on each power wire?

deruvian

Today I was just thinking about the way fuses work (when the fuse reaches a certain temperature the link breaks, opening the circuit). I wonder if it's possible that either the fuse plastic assembly itself is heating up a lot due to being in the engine bay, or that the power wire to the fans heats up too much (thereby heating the fuse too), or both.

Would the insulation on the wire really protect it enough from the heat of being near the radiator, especially for long drives?

I know, I'm grabbing at straws, but I'm just really trying to figure this thing out so that I can stop being worried and annoyed! Any thoughts?

romeo291

iTrader: (1)

Man, I wish I could help you out but I am having this EXACT same problem. My fuse keeps blowing and it's getting pretty frustrating.