W140 A/C Problems

[keitharm]

I've had a string of problems with the A/C in my 1993 400SEL. It's like the blower motor is smoking crack. It won't come on at all, then suddenly it's blowing full blast. Then for no apparent reason, it'll quit all together.

After reading some of the posts, I figured it was either a faulty temp sensor or a bad control unit. I changed the control unit, and have the sensor on order.

Then today, the blower won't quit even when I turn off the engine and pull out the key. What's that all about? I ended up disconnecting the plug at the blower to make it quit so the battery wouldn't drain.