300M - Air Conditioner

The 1999 300M is not producing cool air today... suggestions and ideas most
appreciated. thanks in advance. Ralph Griffith

 

The evaporator went out twice in my 2000 300M. Seems to be a common
problem.
The dash will have to come out for repair.

 

Was wondering if this is better repaired by a dealer or by a ac shop?

 

That is very much dependent on the integrity and competence of the
candidate dealer or a.c. shop. If good - either one. If bad - neither one.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

dealer big bucs! ac shop lots less

 

Try this:
1. Start the engine but do not move the vehicle.
2. Set the Temp control to 75 degrees.
3. Press and hold the Floor, Mix and Defrost buttons at the same time.
4. The control head will begin to blink and enter a diagnostic mode.

Once the unit has gone through its diagnostics it will either return
to its normal mode (with all air doors calibrated) or it will return
one or more of 16 different error codes between 23 and 51.

 

in the fuse panel is a ten amp fuse that sitrs higher than the rest,marked
mi pull it out and leave it out for a minute then turn key on and install
fuse this will reset the bcm and hvac controllerand the hvac will retrain the
motors
there was a issue with keyfobs and the freq. the motors worked at causing
some
software lock ups when using the keyfobs

 

Thanks to each of you for your insight and advice... The end result required
a replacement Compressor, valve, belt, etc.. for just under $1000 total for
parts and labor ... and now the weather is turning cold again! This site is
very helpful..thanks again. Ralph Griffith