EFans keeps blowing relays! Wires getting too hot. t

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M3PO

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If you have a brand new relay installed, do you wires get hot?
I have seen some relays corrode, causing resistance. Pop the relay open and check the contacts and see if it has corrosion, or more accurately, measure resistance across. At the very least, look at the contacts, and sand with a thin piece of emory paper.
Note: this is "drawing straws" but there is a chance your relays are getting wet and corroding contact points which raise resistance.
 
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New relays, sealed relays also. Positive wire from battery gets hot, along with lead to fans. Eventually entire relay gets hot, and I melted another relay today. Again, I didn't have this problem for the last year, but all a sudden, huge increase in heat, but not sure if that's the reason for melting relays. Today, I melted another relay, luckily both didn't go.

How do I go about checking resistance and amps? Do I need an ammeter? thanks guys

---------- Post added at 11:42 PM ---------- Previous post was at 11:06 PM ----------

Ok, so I went and redid, ground wires to ensure good connection, for both fans ground, and relays. Right now only have 1 fan running, but when I turned it on, the main + wire from battery to relay, it got pretty hot in 1 minute???? WTF???? what is going on??? I do have 12ga inline fuse holder going from + bat to relay w/ 30 amp fuse. Too small of wire for +?? Is that why getting hot?

I only have 1 fan connected. It has 12 ga wire from + bat w/ 30 amp fuse inline to relay, 10 ga ground wire to relay on frame, 10 ga wire + lead to fan, and + trigger switch off ignition. Anything sound wrong? Why so hot? what do i need to do? HELP
 

MeanGreen03

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Have you tired bypassing the inline fuse? Is your connection at the fan tight and no corrosion on the connections? I assume you spliced into the pigtails of the stock fans and inline fuses, if so did you solder the wires or use butt connectors? Is all of your wire new or did you use old/used wire?
 

M3PO

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Have you tired bypassing the inline fuse? Is your connection at the fan tight and no corrosion on the connections? I assume you spliced into the pigtails of the stock fans and inline fuses, if so did you solder the wires or use butt connectors? Is all of your wire new or did you use old/used wire?

All good points, if you have bad connections, they are going to causes resistance/heat. Also the more wire and connections the more resistance/heat.

I did a quick google search and there are sites out there to help you size wire for the job, but what you will need to know is the amp draw of the fans. Yes, you will need a meter to measure, unless you can find specs on your particular fans.
You have major resistance somewhere if your wires are heating up instantly like that.
 
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I got brand new 10ga wires, all soldered to connections, I cut pigtail wires and soldered my wires to them, so I have already insured it's not bad wires or connections to wires, great point tho.

I will try and bypass the fuse to see if that may be causing too much resistance in connection causing it to heat up. Like I said, got pretty hot in 1 minute, with only 1 fan on, in regards to main + wire coming from battery thru fuse. Seems like It is trying to DRAW more power thru + battery wire then it should. Just seems weird since other fans I have don't do this. I am getting at a loss here about why? I get increasing wire size will decrease resistance, just don't think going to a bigger wire when OEM pigtail wires are only 10 ga. I shouldn't have to go bigger then OE would? Right? thanks guys
 

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10 ga should be perfectly fine. Try bypassing the inline fuse with 10 ga wire and see what happens. If it still gets hot, and all of the connections are tight and clean as you say, I would try a higher amp rated relay. EIther way check to see how much current the fans are drawing. It would make sense if one fan was going bad and kept burning up the relay going to it, but to have both of them go bad at the same time (especially with that low of miles) would just be bad luck.
 
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1+!!! LOL, would be quite BS if both fans are bad, like you said, are extremely new, and worked great when pulled from silverado. I will try running directly from + batt to relay with no fuse, and see what happens and let you guys know. thanks
 

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If you have a DMM, I would measure the resistance on each motor. If one is greatly higher or lower than the other then maybe you do have a bad fan motor.
 

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