The fan's ground connection may be corroded, which can cause the fan to intermittently stop running.

If cleaning any corrosion from the fan's ground connection does not solve the problem, then start the engine, and turn on the A/C. This will cause the fan to run continuously. If it runs continuously and the engine does not overheat, then the fan's high speed circuitry components and the engine's cooling system components are ok.

If the fan does not run(or runs intermittently) with the A/C on, then one of the following is causing the problem: bad fan motor, bad high speed relay, bad/loose high speed electrical contact in the connector on the side of the fan shroud(or somewhere else in the high speed electrical circuitry), or a bad high speed PCM component.

If the fan runs continuously with the A/C on, and the engine does not overheat, then turn off the A/C and keep the engine running. If the fan does not come on(or it runs intermittently), then one of the following is causing the problem: bad low speed resistor(built into the fan shroud), bad low speed relay, bad/loose low speed electrical contact in the connector on the side of the fan shroud(or somewhere else in the low speed electrical circuitry), or a bad low speed PCM component.

 

Good luck and keep us posted!

 

Isn't this a pretty common problem on the S197? Something about a short in the fan housing/resistor or something along those lines?

 

First I've heard about it...? Living in AZ I would think it would be old news to me if that were the case.

Battery's dying in a couple years...yep, get that all the time. On my 4th one right now in 5 years.

 

I havent heard of it being common place either in the 197. The previous gen yes. It would melt right at the fan and then no fan... Had that happen twice.

 

I'd remove that ground and sand the paint underneath, just for good measure.

someone else had a problem with the fan and the underside of the fuse box was shorting out, so life up your fuse box and check it.

 

I found the problem. This is underneath the high speed fan relay. Does anyone know the part number for the fuse block this is connected to? I have done some searching but came up with nothing. Any helpful info on making this fix would be highly appreciated as well.

 

http://www.fordparts.com/Commerce/Ca...Mustang#Search

Looks like the Fuse Box Retainer (PN 14536) or in the general vicinity. I'd find out what caused that melt down before just replacing. That's not typical unless the relay shorted out internally.

 

Unfortunately it looks like the part I need only comes as part of item 14A068A for $300 ($200 at Tousley). I am going to hit the junkyard next weekend and see if I can get a hold of just the plastic part I need.

From my research it looks like this could have been caused by running my fan speeds at too low of a temp. I have a 170* thermostat and had the fans set at 180 Low 186 High.

Once I get this fixed I am going to run them at 185/195 in case that was the issue. My goal is to keep the temps below 200. At the prior setting I was hanging around 195-197.

 

Ah that sucks ($200+) have you checked e-bay? My daughter recently inherited my wife's 06 Ford Escape and I've had to replace a whole mess of parts like the sunroof frame, cowl vent panel, both sun visors, and e-bay saved me a ton of cash so far.

I'm sure if you find a wrecked mustang online and show exactly what part you need they'll pull it for you for probably Less than $50-$75 shipped. It's not a wear item so new or used should make no difference as long as it's not fried like yours.