you can buy a chilton/mitchell manual or CD and it will tell you the location and troubleshooting procedures. Sometimes local libraries have them available to checkout.
Its located next to the blower motor housing and its called a power unit.....
where is the blower motor resister located on an 2004 s40
how to replace the thermostat on a 1999 Volvo s70
Location ac compressor relay 940 volvo
under the ashtray
No difference....
The fuse should be under the hood in the fuse panel it is #32 on the 97 850 sedan. blower speed 4 is on a separate fuse. I had the problem of speeds 1,2,3 not working and the culprit was the balast resistor. it is ceramic unlike the metal coils used in the American cars. the ceramic deteriorates and the wires break inside the resistor. see answer for ......Where is the air and heater blower relay located on a Volvo 850?.... to find out where the resistor is located.
is it silver? the new one is
Built in in the hazard light switch.
I posted pictures on the location and replacement of an ambient temp. sensor for a 2001 S40. Google "ambient temperature sensor location/replacement" or go to Matthew's Volvo site and search there.
under the glove, you have to download all the glove in the bottom to see a connector achieved it leads to the same AC Blower Resistor