1987 240. My blower fan is making an annoying sqeak, of course, so I thought I would wire a simple off switch in until I could get around to replacing the motor. I pulled #3 fuse, and now the fan doesn't run in the higher switch positions, as I expected, but DOES still run, slow and noisily, in the lowest ( furthest left ) switch position.

Fuse in: runs in all switch settings, faster in the higher ones
Fuse out: runs in furthest left switch position, not in any others

So, I'm confused. I guess either there are two power circuits to the motor, or there are two motors, or my car's wiring is messed up. Can anyone clear up which it is, or some other possibility I didn't think of ?

Is it possible to simply put an on/off switch in the fan switch circuit, so I can turn it completely off when I'm not using it, and turn it on to send power to the stock fan switch ? Or, is it more complicated than that ?

Thanks for any assistance. I searched under variations of fan and switch, and found all the posts about replacing the motor, but didn't run across any that seemed to be about this . . . .

Chris