DIF Controller Melting Inline Power Fuse

[Sileighty_85]

Alright so ive been having a little issue lately with My DIF Controller melting the fuse (30 AMP) and holder.

Bought it New, Used all Supplied Wires and Hardware, had it on the KA for a few months worked great never had issues they ran constantly due to the OEM thermostat, always stayed at 80* C.

Dropped in the RB, had to use the Overide switch since my Coolant temp sensor was bad.

When both fans run after a couple of days the fuse and fuse holder will Melt.

Ive replaced the fuse holder 2-3 times now, Ive even gone as far as Soldering the wires to the O-ring Terminal cuz i though maybe it was a poor connection.

Power and grounds are both connected directly to the battery.

All other wires and connections stay cool, Both fan power wires and Grounds.

I now got a new coolant temp sensor so it kicks on at 80*C and kicks off at 65*C (Nismo Thermo) so they dont run constantly, Still having somewhat of an issue, current holder is showing signs of over heating.

The fuse and holder will melt before the fuse pops.

The DIF Box Get pretty hot as well, and its away from big heat sources



I keep the covers off and it helps a little bit

It seems like I need a bigger gauge fuse holder wire but havent found one yet.




Anybody had this problem?
Is my Controller Bad?

My only theory behind this is that my A/C Condenser/Rad setup.

I was thinking that due to the fin construction on the A/C condenser it pretty restrictive putting more of a load on the Fans, but that should make the Fan wires hotter (but they are not)

[krappy]

your fans are drawing too much current, you need to run lower gauge wires...

[Sileighty_85]

Originally Posted by krappy

your fans are drawing too much current, you need to run lower gauge wires...

Worked fine on the KA, These are the wires that came with the Kit, Both Fans pull 14-22 AMPS and the DIF Controller is Max Rated at 30AMP's so the Fans cant be drawing that much.

All wires and connections came with the DIF Kits so it would be stupid if DIF came with parts that are not sufficient enough

[Hashiriya415]

You could use an amp meter/probe to find out how much current is being drawn. Could be that your fan(s) are going bad. Maybe something stuck in the fan, check to see how the fan(s) spins by hand.

[Sileighty_85]

Originally Posted by Hashiriya415

You could use an amp meter/probe to find out how much current is being drawn. Could be that your fan(s) are going bad. Maybe something stuck in the fan, check to see how the fan(s) spins by hand.

Fans are brand new FAL 420 S-Blades, Fans spin fine by hand and work great when they kick on.

I forgot I have an Ammeter laying around, Ill hook that up and see what its pulling.

[LayNLow]

I have the same problem, but I am running 2 altima fans that are wired to run on high. I assume it does this when both of them run at the same time because it doesnt normally do it until I start to really heat the engine up. I am not sure if the DIF controller will be able to handle upgraded power/fuse wiring, it is something I have always wondered about.

[Sileighty_85]

Originally Posted by LayNLow

I have the same problem, but I am running 2 altima fans that are wired to run on high. I assume it does this when both of them run at the same time because it doesnt normally do it until I start to really heat the engine up. I am not sure if the DIF controller will be able to handle upgraded power/fuse wiring, it is something I have always wondered about.

You should find out as well how much AMPS those fans pull.

Upgrading the wires is not a problem at all, a rule of thumb with wiring is when replacing "always use the same size or bigger wiring", never use smaller.

Fuses are a different story always use the exact fuse never use a bigger fuse.

[ej2civic]

try running a better ground to the fans and another one from motor to chassis. I had a similar problem with mine and this helped big time. the resistance in the connections created quite a bit of heat

[Sileighty_85]

I might try and run a extra ground for the fans

But I hooked up an ammeter this morning

Fans pull around 28 amps Which is still within specs of the DIF System


When I unplug one fan it pulls around 14 Amps so they pull Equal amperage

[importdude]

"Integrated relays simplify wiring and provides up to 12 amps of current per output and 25 amps total, reducing extra costs and installation time."
Seems like your cutting it real close
First try lower guage wire.. I never liked the dif.. Use some high quality relays and wire it up yourself would do better than the dif junk

[Sileighty_85]

Originally Posted by importdude

"Integrated relays simplify wiring and provides up to 12 amps of current per output and 25 amps total, reducing extra costs and installation time."
Seems like your cutting it real close
First try lower guage wire.. I never liked the dif.. Use some high quality relays and wire it up yourself would do better than the dif junk

there is a Version D and a Version C

The Version C holds up to 30Amps and the Version D supports 25Amps.

My Kit Came with a 30amp Fuse so im guessing I have a Version C,
There is no way i would put in a higher amp fuse

Im adding an extra ground for the Fans so ill see how that helps out

[Sileighty_85]

So i added an extra ground, No change in Amp pull.

However, The way i have my battery terminals setup (due being in a hurry to get it running and loosing a bolt and will redo later)

I placed the O-ring terminal on the bottom of the main power ring
so it has better contact with the battery, and it doesn't see to get as hot as it did before.

Yes I know it looks ghetto

[Hashiriya415]

any chance that you flipped the fans backwards? so when you drive the wind pushes on them, adding the need for extra power and you pop your fuse all the time. There is a little difference between the KA and RB setup, KA you had them pull and RB push. If you can, run your ammeter in cabin and see what you get. You could do a 35amp fuse, cuz your on the border with the 28amps, if that was with car off then it will be higher when car is on due to higher voltage. with a 35amp it will make your defi box run hotter, shortening the life.
Ground theory, you guys have to understand that sum resistance through out the circuit will give you a total current(ampere) draw, so with lower resistance in the circuit more current will be drawn, providing a better ground means more current will flow through, compared to a bad ground that has higher resistance. What you could do is put a resistor on the ground side to drop the voltage down a little bit. It will lower the speed of the fans but you won't pop the fuse cuz the current will go down. Or wire up a set of relays, so the defi box doesn't directly power the fans up.

[Sileighty_85]

Originally Posted by Hashiriya415

any chance that you flipped the fans backwards? so when you drive the wind pushes on them, adding the need for extra power and you pop your fuse all the time. There is a little difference between the KA and RB setup, KA you had them pull and RB push. If you can, run your ammeter in cabin and see what you get. You could do a 35amp fuse, cuz your on the border with the 28amps, if that was with car off then it will be higher when car is on due to higher voltage. with a 35amp it will make your defi box run hotter, shortening the life.
Ground theory, you guys have to understand that sum resistance through out the circuit will give you a total current(ampere) draw, so with lower resistance in the circuit more current will be drawn, providing a better ground means more current will flow through, compared to a bad ground that has higher resistance. What you could do is put a resistor on the ground side to drop the voltage down a little bit. It will lower the speed of the fans but you won't pop the fuse cuz the current will go down. Or wire up a set of relays, so the defi box doesn't directly power the fans up.

Nah They are setup as pushers (pusher blades are installed) and wired accordingly.

Ammeter pics were taken with the Engine running and Override switch engaged so both fans running.

Its not an issue with the fuse poping since the Amperage is not being exceed,

I think i solved it with the possibly poor connection at the battery, as you can see in the above pic, I had it on top of the main power wire which seems to have some built up crap on it and that bolt looks to have some kinda coating over it so it was trying to pull 28amps through a crappy connection and all the heat getting built up inside the rubber fuse holder body eventually melting it.

I put the O-Ring terminal below the Main Power wire so its directly on the battery terminal, ran the fans on high for probably 10mins and then a short drive, It got warm but nowhere near the temp it was getting before

[redline240sx]

I am having this same problem with my flex a lite fans, I am using the flex a lite fan controller, since i read that you figure out your problem you mind PM with more specific details? thanks.

[Sileighty_85]

Originally Posted by redline240sx

I am having this same problem with my flex a lite fans, I am using the flex a lite fan controller, since i read that you figure out your problem you mind PM with more specific details? thanks.

basically just make sure you have good power connections

[Sileighty_85]

Seems the Version D couldnt handle the Amp draw so upgraded to the DIF PWM controller (rated at 60Amps) and haven't had a issue since