Blowing Fuses

[kpack5982]

So I noticed that I am constantly blowing the fuses to my controller/relay. i have a 30amp fuse in there and I bought one of the temp control units from o'reillys. One thing I noticed is that the wiring is a lot smaller on the control unit, but I went ahead and wired to it anyways, relying on the fuse. But it keeps blowing. Also my fuse for my radio/interior lights blows when the fan kicks on, any ideas or suggestions?

 

[jrichker]

Is the fan wired corrrectly? Do you have only one power lead and one ground lead for the fan? You should be using 10 gauge wire for the fan power and ground.

Do you have a 3G alternator? It is very difficult to run the fan on the stock alternator without using a DC Control or similar high quality controller. The starting surge current on the fan can run from 70-100 amps.

 

[kpack5982]

yes, yes, and yes, except I am going to run a wire from the ground on the from from the back of the car to the block and run a bigger bolt on the grounds in the front. I am also going to connect a surge suppressor diode, but do i just soder it in and cover with heat shrink or how do you do that? I'll see if that helps.

 

[bullitstang1313]

How exactly do you have the controller/relay wired. The 12 volts supply to the coil-side of the relay shouldn't need any protection greater than 5-10 amps. If you have a 30 amp fuse there and it keeps blowing then you have a short somewhere in the circuit. On the high current side of the relay you should have larger wiring and a larger fuse or possibly even a circuit breaker. As jrichker mentioned above, the starting current of the fan can get as high as 100 amps so a simple relay setup is not the best way to control an electric fan.

 

[kpack5982]

I have a fan control I bought from O'reilly's HAYDEN, INC. - Cooling Fan Control
Item No: 3647. It didn't have as big as wiring as the 10 gauge I bought, but here is how I wired it:

One 10g wire from the solenoid to the control/relay, there is a 30a fuse on the control line there. From there it goes to the power on the fan with a 10g wire.

one 10g wire from the negative on the fan to the ground where the battery used to be.

One wire from the control to the 12v power on of the low coolant sensor. '

One ground from the control/relay to the battery ground.

Right now I don't have the a/c hooked up so that is all the wiring there is. There are about 5 different wires grounded to the battery ground. Only problem is it is just a self tapping screw holding all the wires onto the ground spot.

I bought a surge suppressor diode from radio shack and am going to wire that in, but I don't know how to connect it, as mentioned above to help, I assume with the pull of the fan when it starts up.

I was thinking about changing the ground on the fan to a spot over on the passenger side, but don't know if that would work or not. I mean, where could I ground to there?

 

[HISSIN50]

What relay terminals do you have a given wire hooked up to?

Using conventional nomenclature, the control side (thin wires - one from the coolant bottle and one from the controller) go to 85 and 86.

The load side go to 30 and 87 (fused power from the battery and a wire from the controller to the positive terminal of the fan).

 

[kpack5982]

That's the thing, the controler comes with a relay on it, and it is all wired via the controller. Everything worked fine when I simply had a relay hooked up and power on whenever the 12v key on was on.

 

[jrichker]

The Radio Shack suge supressor is just for a radio or other low current audio equipment. The primary purpose is to drain off the electrical noise on the power feed to such equipment. It is not intended for use with an electric fan used to cool the engine.

The diode absorbs the electrical spike that is generated whn power to the fan is turned off. It does nothing to dampen the inrush of current when a fan is first turned on.