Fan relay keeps blowing/melting WTF?
 

Hey guys, My 07 Mustang is blowing fan relays like it's going out of style. The only thing that I've done since the problem started is at clear corners, HID Bi-Xenon kit and Pypes headers.

The local mechanic says it's got to be the HID's but didn't even look at it :icon_angel:

The HID kit is wired directly to the battery not the fuse panel and it has it's own relay , in-line fuse and it's connected to distribution block with another 100amp fuse and they are all fine. The only place the HID ties into is the factory bulb harness and nothing more.

Could it be a bad fuse box?

Anyone else have problems blowing their relays?

I'm at a loss here and can't afford for the car to keep blowing relays and all of the antifreeze everywhere.

Thanks in advance!!!!!

For the life of me, I don't know how the HID's could be the culprit. BUT, I'd disconnect them for a few weeks and see if the problem occurs again. I haven't looked at the wiring diagrams for this but I'd at least check for any suspicious wiring issues, unexpected voltages or grounds.

Tough one. Good luck.

I did just that and disconnected the HID kit and put the stock bulbs back in to see, but I doubt that can be the culprit either.

I filled the car back up with antifreeze and put the relay back in and the fan was running and noticed the fan relay was the only relay that felt remotely warm without the HID kit hooked up:icon_emm:

When I installed the HID kit, I did disconnect the ground as instructed, however I do have a tune on the car and didn't check to see if the tuner has anything to do with it:icon_shrug:

The car is running like poo right now, however I believe it goes into a safe mode when it starts to overheat as stated in the manual.

THIS SUCKS!!!!!

Disconnected the HID's and put them back to stock, installed new relay and antifreeze and low and behold it did the same thing on the way to work this morning so it's not the HID's.

I think I need a new fuse control panel and the local scrap yard has to 05 Mustang 4.0 there that I can go and pull it off, not sure if the transmission would have to be the same or if the boxes are different since I have the 07 Mustang???

Or

I can get a new one from Ford (puke) for $301.66 :(

Any advice?

Something is drawing more current - why else the burnup of relay? I don't see how it could be the fuse panel unless there are corroded contacts for that relay, but I still really don't see that as a problem, doesn't corrosion increase resitance?
Would anyone suspect the fan itself? Seems to me its the unit (the fan) pulling the current and somehow now pulling more current to make the relay fail... Amp meter in the fan circuit is the only way to actually test what it is drawing and compare that to the specs for the relay..

First off, RTFM about battery replacement and follow
the adaptive relearning procedure and the poo will
disappear.... It only sucks as bad as you MAKE it suck..
Suck it up and read the forkin owners manual.
Wipe the tears away.... Daddy will make it all better....
Define "blowing relays".
Do they litterally blow up with percussion and smoke?
Whats this 100A fuse all about?
Your local mechanic is just that.
Not a automotive electrician. Most dont know squat bout
mobile electrical systems and just guess and replace until
the problem either disappears or the vehicle outlives its usefullness,
which ever comes first... :) LOL
The HIDs have nothing to do with your fan relay overheating
problem.
Check the amperage draw on the fan.
Is this the low or high speed relay?
Are the proper sized fuses installed
for the low and high speeds?
Can you read a wiring diagram?
Are you sure its not the PCM power relay thats getting warm?
I need fuse #s and relay #s to internet diagnose the problem...
Are you running a tune? You didnt happen to disable the fans
by any chance with a tuner? Does the problem coincide with
a tune install?

100 A fuse is kinda large isn't is? Sounds kinda like a short on the ground side to me?

im having this problem with my 06 gt did you fix it if so what did you do..

You DO realize this thread is about 3 1/2 years old and the OP has only a 12 post count....

James is new, so I'll cut him a break. But this really is super old.

Check out the heater motor and resistor. One is drawing too much amperage, causing the relay to pop. Most likely the heater motor is the culprit. They tend to get dirty and draw excessive amounts of power. Good luck.