Is there a fuse for the volvo 940 altenator ?

check the fuse .and all of the bulbs are working.if ok then change the brake switch.

Underneath the alternator facing forward is a 13 mm nut which locks the alternator in place, slacken this off and the two nuts/bolts where the alternator pivots.From the left side of the car there is a 10 mm bolt which is the tensioner, slacken this untill the alternator can be moved towards the engine sufficiently to remove the belt .Reverse this procedure to replace the belt. (depending on drives to other items you may have to remove their belts as well)

im not a 100% on this but if you got a crank sensor on there i would check that ...if its bad it will put no spark to the car

the BOO switch, (Brake On Off) located on or near the brake pedal

if the fuse is good i could be the switch itself take out one of the switch and check wires with volt meter

change your speed sensor

ok, this used alternator has bad diodes and will need them replaced. sometimes, certain technicians wont rebuild correctly. they just look over this vital part. i would return this alt.

It is possible you are looking at the page for the 1994 960 and not the 940. The 960 had one (serpentine) belt. Your 940 has three. Hopefully chiltons has the repair order for the 940s as well.

I know it's not alot, but I hope it helps

Change the the O2 senor on the catalytic convert. Its probably dead.

behind fuse panel big red round relay and you can normally solder bad connection inside if you look close