2010 S40 Blowing fuse 35

projectjim · Post by **projectjim** » 20 Sep 2013, 08:10

I'm new to this site, and recently purchased a 2010 S40.Everything was fine for about 3 weeks. About a month ago the check engine light came on. It had codes p2420,p2401,p0075,p0458,p0100 stored and the a/c quit working (all at the same time). Fuse 35 was blown. Put another fuse in and cleared codes. Car was fine for 2 weeks. Same thing again. Looked around the wiring to the a/c compressor and tried to move it around a little bit think it might be occasional short. Replaced fuse again and 9 days later same thing again.Does anybody have any ideas??Possibly the A/C clutch occasionally shorting out?? Any help will be appreciated.

Post by **jimmy57** » 20 Sep 2013, 09:56

Remove fuse and probe with ammeter at the two fuse terminals in fusebox. Have someone start the engine with a/c off. See what current flow is through that fuse and then have your asst switch a/c on and see what current flow is with compressor clutch on. The clutch current should not be more than 4.5 A and will normally drop a bit after a few seconds as clutch winding warms up and resistance builds and drops current down to 3.5 A. If it is the clutch it will almost certainly be out of range when when the fuse doesn't go open.

Is the car out of the 4 yr/50K mile warranty?

projectjim · Post by **projectjim** » 20 Sep 2013, 11:15

jimmy57 wrote:Remove fuse and probe with ammeter at the two fuse terminals in fusebox. Have someone start the engine with a/c off. See what current flow is through that fuse and then have your asst switch a/c on and see what current flow is with compressor clutch on. The clutch current should not be more than 4.5 A and will normally drop a bit after a few seconds as clutch winding warms up and resistance builds and drops current down to 3.5 A. If it is the clutch it will almost certainly be out of range when when the fuse doesn't go open.

Is the car out of the 4 yr/50K mile warranty?

Unfortunately the car has 54,000 miles on it. It had just run out of warranty when I bought it. The original fuse (calls for 15 amp) I pulled out did look to have been in the car for a long time though(color on the prongs).I will try to get the amperage on it this evening. Don't know why I already didn't check that??

My thinking was more of an occasional short in the wiring. I'll post results when I check it this weekend. Thanks!!!!!

projectjim · Post by **projectjim** » 24 Sep 2013, 05:16

Sorry to be so long getting back to you. I had to borrow a meter to do this. On fuse 35, I am only getting a .8 to .9 amp draw when the a/c comes on (relay only?) . On the a/c fuse I am getting a 3.0 to 3.2 amp draw with the a/c running. I am guessing since the fuse that is blowing(fuse 35) is only the relay for the a/c then maybe it's something else. If it were something in the a/c shorting occasionally ,wouldn't it blow the a/c fuse too? Do you suspect wiring or possibly a sensor?
Thanks, Jim

projectjim · Post by **projectjim** » 16 Oct 2013, 07:12

Update... I went ahead and took a chance and replaced the relay for the air conditioning. I'm not normally a "parts changer", but was to the point I had to do something and it was a cheap gamble . That has been 3 weeks and so far all is good. I will let you know if anything further happens. Thanks,Jim

projectjim · Post by **projectjim** » 25 Nov 2013, 11:41

Well after nearly 60 days, the fuse blew again today. It does seem like(not 100% sure every time) when it happens that we have been changing the temperature setting on the climate control. Any ideas????

Thanks,
Jim

projectjim · Post by **projectjim** » 25 Nov 2013, 11:44

I forgot to add that a/c is on a separate fuse. The a/c relay as well as some of the engine management is on the fuse.

80sGuy · Post by **80sGuy** » 25 Nov 2013, 13:49

Seems like there's a short within the AC unit. I think it's best you take it to an independent shop and let them diagnose the problem.
I just picked up a nice 2009 S40 2.4i too. So far so good besides the ABS module noise whenever the car starts rolling within 10-12mph (from the first ignition), but that's it. Oh yeah, gas mileage sucks!