Heat/Air controls

Today, as my wife was getting ready to take some visitors to the zoo, she
noticed that the temp readout on the heat/ac panel of her '99 300m was bad.
When trying to set the automatic control to 72º, it would go up the scale to
32º then just read "Hi". I messed around for a while and couldn't get it to
work right. I'll hear about it later if it gets too hot or too cold on
their trip.<G>

Any ideas? I spent a half hour on the 300 board, but didn't find the
problem discussed. I'm hoping you're reading the ng Bill.

Jim

 

I don't know anything about them newer ones, but, is there an option to show
temperature in Celsius or Farenheit? Have an Owner's Manual?

Larry
Behold Beware Believe

| Today, as my wife was getting ready to take some visitors to the zoo, she
| noticed that the temp readout on the heat/ac panel of her '99 300m was
bad.
| When trying to set the automatic control to 72º, it would go up the scale
to
| 32º then just read "Hi". I messed around for a while and couldn't get it
to
| work right. I'll hear about it later if it gets too hot or too cold on
| their trip.<G>
|
| Any ideas? I spent a half hour on the 300 board, but didn't find the
| problem discussed. I'm hoping you're reading the ng Bill.
|
| Jim
|
|

 

I've posted here before about the problems I've had with my 2000 300m.

Specifically, (and it will only happen maybe once every winter) while
driving (usually highway) during snow/sleet/ice storms where snow
buildup happens on front (and maybe under) the car, the external temp
readout will drift upwards (from the 30's to the 50's) and the
interior air will start to blow cool air (even when manual temp
control is set high).

There seems to be some sort of connection (mechanically or
programmatically) between the exterior temp sensor and the internal
heat controller.

 

Y'all found the problem. Daughter borrowed the car yesterday, and in trying
to find the garage door opener, punched all the buttons up top. Reset to
ºF and all is well. Thanks for the responses.

Jim

 

the system is capable of storing and recording fault codes in the hvac module
and the bcm and thats were you should start before any money is spent
but hey wait i just remembered something
pull the cover off the fuse box on the side of the dash then look for the red
fu10 amp fuse that sits higher than the rest and pull it out for 10 minutes then
reinsert fuse and start and run vehiclke see it resets hvac module so it can
retrain itself