Hi, First let me say thank you for helping me through my first year as a proud 240 owner!

I decided to finally put in a blower motor I had sashed away over the summer. Since I've had the car, the fan only has work on speeds 3 and 4 (somewhat loudly). Once I had the motor installed, I had a much more quite motor but still only running on only 3 and 4 speeds. The resister was replaced 3 years ago by a mechanic who spiced out the old resister wires and ran the leads to the new resister he put out on the side of the center console. So I took the original resister hooked it up the the switch an the motor behaved exactly the same as the newer one? Now as I understand it, the resisters have individual thermal fuses and elements that burn out? I checked out the wiring, which seems okay. I cracked open the fan switch (which was replace when the resister was) I lightly resurfaced the contacts and sprayed it down with electrical parts cleaner.

So bad switch, resister, or wiring? Any test to pinpoint the problem or advice would be greatly appreciated.