405 Heater Door Motor
Jim Lill (jpl@vectorbd.vivanet.com)
Sat, 19 Apr 1997 15:21:22 +0000 (UTC)
In spite of the low (27K) miles, a few years ago the heater door motor on
my Mi16 became erratic. As I do not drive it in the winter, I've never
done anything about it until now. The synthoms are: it started with a
burning wire smell that I didn't pin down at the moment it happened. Then,
I found I had no heat. This year, in the cool spring, I found all of a
sudden I had heat all the time (temp knob at full red). For a few days, it
worked normal, then partial unadjustable heat. My theory is that one
winding the the motor which I'll bet has a 3-segment commutator is burnt
out (who knows why). And if it comes to rest on that one, it's dead until
it gets jarred to a live pair on the commutator.
Yesterday, I had a discussion with my mechanic on this and he said
guessing don't do it, better to unplug the motor from the ECU and sub in a
working motor or ECU to zero in on the culprit. That makes sense. Better
though is a trick he showed me on how to access the motor area. Clean out
the glovebox and with a hole saw cut some access ports in the left wall,
the motor is directly behind it. With that done, you can access the
connector for sub'ing and eventually if you need to, remove the motor.
When done, there's a number of ways to acceptably cover the holes.
Any opinions on my door problem and/or this fix method?
-Jim