A/C 10 amp fuse keeps blowing......

1CleanLs

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The ac on my 03 ls worked great the first 2 weeks I owned the car and then the ac started to blow hot air. The 10amp fuse under the hood blows as soon as I put a new one, any suggestions on what might be the issue? Also sometimes (not always), after I drive the car for a bit and turn it off for a few minutes and turn it back on, temp gauge goes to Hot and fan turns on and returns to normal......dont know if its related to hot air on ac. Thanks
 
Actually, the most common cause of this has been posted several times on this board.

DCCV leaks a minor amount of coolant into the DCCV solenoid coils.
DCCV solenoid coils short out.
AC clutch and DCCV soleniods fuse blows.

Of course, there are other possibilities. It could even be your AC clutch or the wiring. You should unplug the connector to the DCCV and replace the fuse. If the fuse doesn't blow, then you pretty much know that the DCCV needs to be replaced. Please note that when you do this, even if the fuse doesn't blow, your AC still won't work because the disconnected DCCV puts it into full heat mode.

Location of DCCV:
http://deneau.info/ls/s6x~us~en~file=s6xc1014.htm~gen~ref.htm
 
Would that cause the overheating issue as well? It never overheats while driving, only once in a while when I turn it off and back on after a few minutes. Thanks for the reply!
 
Would that cause the overheating issue as well? It never overheats while driving, only once in a while when I turn it off and back on after a few minutes. Thanks for the reply!

A cooling system leak that lets air in would explain your overheating. While it is possible that only the DCCV is leaking, it is very likely that your degas bottle is cracked and needs to be replaced. You should also check the plastic cooling system parts at the front of the engine for leaks. There are many threads on this too (please, at least read the stickys), you are unlikely to be the exception.
 
I dont mean to sound ignorant, but what do you mean by reading the stickys? I am new to posting on forums, lol
 
I dont mean to sound ignorant, but what do you mean by reading the stickys? I am new to posting on forums, lol

Sticky at top of forum.

sticky.jpg
 
Hey guys, sorry to bring this old thread back from the dead.
In my everlasting journey to get my LS running perfectly, I have a question about this fuse and DCCV. I replaced the DCCV just a couple months ago. It has stopped working for some reason. I looked to check the fuse, and it is was blown. When I replace it, I can hear a popping, which I assume to be the solenoids waking up? It will work as it should but will shortly blow back out (the fuse) in a day or two. I'm wondering what could cause it to keep blowing the fuse?

TIA
 
Usually, it is because the solenoids in the DCCV are shorting out internally due to coolant leaking into them.
Of course, it could also the compressor clutch or frayed wiring.

If you unplug the DCCV and replace the fuse and the fuse hasn't blown after a few days, then it's likely to be the DCCV. I tried an aftermarket DCCV once. It only lasted a month or two. I have a brand new aftermarket DCCV (lifetime warranty) sitting on the shelf now that I will never use.
 
Hey Joe,
Thanks for the quick reply (as always).
I purchased a OEM Motorcraft YG378 Heater Valve from Amazon, end of Sept. '18. (do you happen to know if Motocraft would honor some type of warranty, in case the DCCV is faulty?)

Did I make a mistake in replacing the DCCV before focusing any of my attention on my AC system (clutch/compressor)?

I have yet to hook the manifold gauges up and test my pressures out but, while the part was so cheap on Amazon at that time, I decided to purchase it then, and obviously install it. For about 2 months, it worked fine; I was able to change temperatures as I pleased, within warm-hot. Now lately, it is just straight hot. When I replace the 10amp fuse, it will work again as intended, but usually blows within a day, most recently, will just be blown out the next time I start my car.
 
With Amazon it's up to whichever seller sold you the valve. It won't be Motorcraft's problem unless you purchased it through an authorized Ford dealer (on-line or brick and mortar). Even then it would have to go through the dealer, you couldn't go directly to Motorcraft.
 
hmm..I'll have to look more into it. When I log into my Amazon account and go back to that order #, and click on support for that item, it brings me to a page that says to contact the manufacturer. When I check the seller, it says Motorcraft: I wonder if they have a contract with Amazon to sell their products.

Could the A/C system not currently working cause the DCCV to break prematurely? I'll disconnect the DCCV connector tomorrow after grabbing some more 10amp fuses and see what happens. Thanks again, Joe.
 
Grabbing fuses on lunch break and will report back. Only other thing I can think of, the upper radiator hose split/burst a hole in the middle hard plastic area where it turns down into the other hose, coolant went everywhere. Not sure if coolant spray on top of the dccv could mess it up?
As always, I appreciate you guidance!
 
It shouldn't, but who knows...
Not sure why but, that made me chuckle.

I’ve seen you say a few times how it leaks into the solenoids and shorts it out. I’m trying to understand what that means. Does the hoses running into the dccv leak inside the actual part? Maybe the coolant spray that occurred when the hose burst somehow leaked in? I’m trying to understand how it just stopped working. How the dccv actually breaks, and if there’s an underlying issue. End rant
 
The valve leaks coolant internally into the coils. I would expect them to be sealed well enough the water sprayed onto them from outside would not be a problem. (I would expect submerging the valve is water to be a problem.)

Of course I would prefer the valve to last forever, or at least 300K miles. I know it wouldn't be impossible to make one that does, but I don't know how much more it would cost or if I would be willing to pay for it. I do know that I would much rather replace a DCCV on an LS than an air temperature blend door (whole dash has to come out) on a Town Car.

I had one that was bad from the start on a new 1991. It was a weird failure. It wouldn't go to the heat position when it was very cold in the car. It was sticking. It took them three visits to figure it out and fix it. The first two times they kept it in the dealership garage overnight, so it never got cold enough inside the car. After the 2nd failed attempt, I realized that warranty or not, I was going to have to figure it out. I did, while they didn't completely take my word for it, they did at least leave it outside over night, and were then able to see the problem themselves the next morning.
 

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