Heater/AC Blower Motor Switch Problem

Excessive current draw causes arcing and heating. So does loose switch parts that bounce. I would find out how easily the blower motor spins.

Good answer! I've heard that for my year (2000 Sonata), there have been electrical problems. Sure enough, a few of my dash nightlights are dark due to some sort of contact failure and my rear electric windows won't operate from the driver door switches: all intermittent. Crappy parts, say I. And it may just be that these switches leave the switch factory with a coating of schmutz on the contacts that oxidizes quickly, then the switch fails.

Arcing usually occurs when contacts open, such as when you turn off the heater blower. A little help may extend switch life. Having worked a bit in electronics repair, I like to use a liquid that leaves behind a micro-coating of silicon fluid. This coating forestalls oxidation while allowing conductivity. First, I'd clean the contacts (90% isopropyl alcohol has been working nicely for me) followed by a little hit of the preservative spray. It's usually called by a different name, such as "control cleaner-lube." The spray typically has a liquid carrier that evaporates, leaving behind the silicon film.

It's best to do this when the switch is still in good condition. I'll have to try this remedy myself. The bitchy part for me is that I can open the rear windows from the front door switches, but then I can't close them unless I use the rear switches. Of course, the rear switches get less use and less weather exposure, since the driver is usually alone in the car and he doesn't drive the car from the rear seat.

See if this works for you, then please report back.

Richard

Is there any chance that a "critter" such as a mouse got into the blower and causing it to bind or slow down?

---MIKE---

In the White Mountains of New Hampshire (44=EF=BF=BD 15' N - Elevation 1580')

There'd be a vibration you wouldn't believe.