Volvo Forums - Volvo Enthusiast Forum - Volvo Community - Volvo Repair banner

1 - 2 of 2 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Hello

My wife's 855 which we have had for 6 years has started doing weird things with the fan behind the dash and I would be grateful for any suggestions. It is a manual climate control system. The aircon usually works very well. The aircon compressor was replaced last year.

In very hot weather the fan has started to slow down and then almost stop, accompanied by a complete lack of cooling from the aircon. There is also a strange whirring sound from the fan when this happens.

In normal conditions, say up to about 70F the aircon is great. However, when the temperature get up above, say, 80F AND the fan has been on for a long time the system stops cooling and the fan slows down.

The 4 speeds on the fan work fine at other times so I thought that the fan resistor was OK. I removed it from the fan housing and tested resistance over the thermal fuse with a multimeter checked out ok.

Next it removed the fan unit itself. It spun freely however I thought I should remove the fan cage from the motor and lubricate the bearings. I did this and then replaced the fan in the heater box housing.

However when I connected the electrical connector to the fan it immediately turned on at full speed without ignition on and would not turn off. The fan speed control does not work with or without the ignition on. I have had to remove the electrical connector from the fan to stop it operating.

When I was removing the fan cage I did have to use quite some force with a drift on the motor shaft to get the cage off and I did spray contact cleaner all over the fan motor? I used light machine oil to lube the fan bearings.

Have I killed the fan motor and/or the blower resistor and what could have caused the initial problem of the fan slowing in hot weather and the aircon stopping.

I suspect that I will have to buy a new fan motor and fan resistor.

Any suggestions gratefully received

Chris, Volvo 850 Sydney Australia
 

·
Registered
Joined
·
7 Posts
If the fan spins without the keys in the ignition, it's the resistor. Usually the fan seizes, and that causes the resistor to blow but it sounds like you only have one problem to tackle.

Do you have a cabin filter installed? If not, get one as it keeps detritus from falling into the fan and causing failure.
 
1 - 2 of 2 Posts
Top