Another Kentucky guy but Western Kentucky

monkeyy337 · Post by **monkeyy337** » 05 Jan 2010, 23:37

Just wanted to say hay to everyone. I've got a 1993 black 850 Volvo sedan and its in pretty good condition aside from a problem with something causing the fan speed switch (heating/AC) to stop working. Its really cold here now so will figure it out when the weather gets some what warmer.

Post by **polskamafia mjl** » 05 Jan 2010, 23:48

Welcome to MVS. The fans on the 850 have a tendency to fail after a while. As time goes by the fans lose lubrication on the bearings. This causes the fan motor to draw excess current which blows the power stage or the resistor, depending on what kind of climate control you have. There is a nice discussion about the heater fan on here. This is a link to it -> https://www.matthewsvolvosite.com/forums ... 22&start=0

That should give you more information on the blower unit.

monkeyy337 · Post by **monkeyy337** » 06 Jan 2010, 00:06

The fan on my Volvo is super quite and works fine but you may be correct in that its pulling to much power. I have only owned the vehicle for about 6 months and I've changed the ECU control panel three times because the fan switch quit working. The one presently in the car also quit working and the system failure lights starting flashing but for some reason two days later it started to work again? I was told by a Volvo mechanic that if I change the blower motor I also need to change the resistor as well.

Post by **polskamafia mjl** » 07 Jan 2010, 14:50

On your 93 you have the Manual Climate Control right? If the resistor is still working you don't have to replace it when you replace the motor. Once the blower stops working completely then you have to figure out what caused it, i.e. did the resistor blow or is the fan fried, or are they both gone.