Re: 405 Heater Door Motor

DON & ANN SMITH (painter@superiway.net)
Wed, 23 Apr 1997 21:45:25 -0700

Jim Lill wrote:
>
> 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

Jim, no answers but wanted to piggyback on your message. My 86 505 has a
problem...the blower motor for the heater/air conditioning started to
shreik continuously today. Past experience with other vehicles led me to
remove the fuse so I wouldn't burn it up. Can anyone advise procedure
for removal and replacement? Can't find a manual here.

Thanks - Don