Fan Blower Occasionally Won't Work

washdup · Post by **washdup** » 07 Oct 2010, 21:48

Yesterday I was driving home from work and noticed the cabin was stuffy so I went to turn on the fan, but then I realized it was already "on", just not working. I got home and pulled/checked the fuses, both of which were fine. Then I turned the car on and the fan worked, so I thought maybe the fuse was not properly seated.

Today, on the way home, the fan initially worked, then stopped and the lights on the slider and one of the buttons were flashing. I went to turn off the fan via the slider and then turn it back on, but it wouldn't come back on. The lights stopped flashing when the fan slider was switched to "off", and did not resume when it was switched to "on". I ran an OBDII scan and no DTCs. I just dropped $100+ today on a new hub from FCP. Is one of these next?

KRUZNBY · Post by **KRUZNBY** » 08 Oct 2010, 06:05

My blower motor resistor was faulty on my 850 ECC controlled. The blower would work, but not at full speed. Sometimes it would not work at all and other times it would. Finally it stopped working completely. It was about $115 from FGP. The slider light never changed for me, but I was able to pull the codes and got 418 something about no power to the blower. Did the blower make any bad noises like it was on its way out?

washdup · Post by **washdup** » 08 Oct 2010, 07:56

No, it just quietly stops working. When it does work, it works fine. It seems to reset once the car is turned off and back on again, but after a few minutes stops. It is ECC, by the way. I don't want to replace the wrong part, and don't want to replace more than I have to. The entire assembly is $199 at FCP. I know the controls are different on an 850, but are the motors the same?

pablotar · Post by **pablotar** » 08 Oct 2010, 11:38

You can always pick up the parts from an 850 in a junkyard, they're the same parts for the fan and the resistor, it' ll probably cost you 30 to 50 bucks. I just picked up a working fan from a 97 850 that had a manufacture date of 2008: cost me 18 bucks and will probably last years.

washdup · Post by **washdup** » 08 Oct 2010, 12:07

Good find! I doubt I'd be so lucky. Seeing that I'll likely be buying new parts, I don't want to buy the wrong part, or an unnecessary part.

nwhitney · Post by **nwhitney** » 08 Oct 2010, 16:30

I believe you need to have a Volvo mechanic pull codes for you. OBD II scanners that we can get won't pull those codes, you need a special computer and they can be spendy little buggers. I had a similar problem and my indy Volvo shop pulled the codes for free. I needed to replace the blower motor and the engine coolant temp sensor. I know that it seems odd that the engine coolant temp sensor would affect the ECC but it can according to IPD and my mechanic. I say get the codes read from a Volvo mechanic versus shooting in the dark. It will save you time and money.

washdup · Post by **washdup** » 08 Oct 2010, 16:41

Amazing the detail codes can provide.

Post by **BEJinFbk** » 08 Oct 2010, 17:52

First guess:
Sounds a lot like a bad motor. It's probably teetering on the edge.
If it goes, it MAY take the power stage (resistor...) with it.
If so, I'd stop running it and replace that motor ASAP.

2nd possiblity:
Have a look at the connectors between the power stage and the motor.
Sometimes they wind up with poor connections and overheat.
That can cause intermittent operation.
If it has, you'll see where the contacts have gotten hot.

But I'd put my money on the motor heading south.

Good Luck!

washdup · Post by **washdup** » 21 Oct 2010, 15:19

Pulled the codes and it was 4-1-1, the resistor. My fan does not make noise, so the code seems to be telling the truth. Priced it at FCP and tasca and Tasca wins by a nose (even with FCP's free shipping and 10% discount).

washdup · Post by **washdup** » 27 Dec 2010, 13:58

Replaced the resistor, no help. Ended up having to replace the blower unit, which did the trick. I got one from FCP Groton for <$100, with lifetime warranty.