Hi, y'all. I'm new to this forum, as I just bought a 98 S90. I've seen people on the 960 forum with blower problems, and am told the cars are similar. The previous owner had problems with the blower staying on all the time, even with the key out. His mechanic removed the blower resistor to save his battery. He purchased a new blower resistor, but never installed it. I have it. I've seen lots of threads for the S90 and 850 series about blower problems, but haven't found one addressing this. Any thoughts or suggestions?

 

Do you have the electronic climate control (ECC) or manual (MCC)? You may also find the wiring diagram useful...

Volvo Wiring Diagrams

Some different things come to mind - bad resistor, a relay stuck in the energized position (not sure which), problem with the ignition switch, a short in a wire or connector etc... I realize pouring through wiring diagrams is a pain but it should give you some ideas on what components are in play.

 

@mt6127 -

Thank you. I should have specified that the system is MCC. Where is the relay located in the car? I may just replace it when installing the new resistor and see what happens. --Jeff

 

I haven't looked at the s90s diagrams for what relays are where, but I'd check the AC relay (s)? (there's a pair of relays up by the top of the radiator on my 850 that's not in the fuse box)

 

for climate control most relays are behind the radio.... just remove the kick plate under the glove box and they will be right there. i would say sounds like a bad relay.

 

Thanks, jands. I'll be digging into it this weekend. Plan to jumper the blower motor just to check it's working with voltage applied, install new blower resistor, and locate that relay. When I get into the relay box behind the console, how can I identify the related relay? I can't seem to find a relay diagram for my 1998, and others don't show a relay for the blower/climate control I wish I could order one ahead of time, but it seems like I'm going to have to locate it, pull it and get the part number off of it to move forward.

I've looked at some diagrams around the internet, and one on matthewsvolvosite.com suggest two relays may be located near the blower -- one for lower fan speeds, and one for high.

http://www.matthewsvolvosite.com/for...ic.php?t=23749

This is, however, for an 850. Can anyone confirm the location on a 1998 S90? Thanks! (Sorry for posting this in the 960 forum, but I'm not getting any responses in the S90 forum.)

 

well the s90 is pretty much a 960 so no worries. as for what relay, i would do a search for a 1996 and above 960/s90 since they are almost exactly the same car (some minor interior changes if i am thinking right.