Why does my A/C blower motor suddenly turn off at random times? It will not re start no matter what I do except if I press "Off" & leave the system off for a couple of minutes... Then the system will work properly sometimes for weeks or months.

When the blower shuts off by itself, all of the indicator lights say that the system is operating. I can even hear the radiator fan screaming to cool the radiator untill I shut the system off.

Happened twice in the last 2 days after not happening for 10 months!

 

It has happened to me also. I think the blower gets tired and just decides to rest every once in a while. It has happened to me several times after I had been on the defrost setting when trying to get back to "Auto". Perhaps there is some Geritol that can be poured into a vent. (how's that for showing my age?)

 

Sounds like a bad sensor shutting down the blower because it thinks the cabin is cool enough. Instead of going to a lower fan speed it's defaulting to "off".

 

..

Happened to me ONCE -- mid winter..

Called the dealer, gave em hell, they took my baby in the same day.. they order and replaced HVAC motors and stuff.. hasn't happened again..

Make a service appointment..

 

If this were the case the fan speed indicator bar graphs would drop down also, as the do in normal operation... fan speed is always indicated correctly graphically when the unit is functioning correctly. They do not drop down in the display, all the indications are that the unit is on & blowing as hard as it can in MAX mode... but the fan has quit & remains off.

When it happened in the winter to me, it was as a result of pressing the front defroster button. The mode changed into defrost, with loud blowing, & then silence. Changing modes did nothing to restart the fan. Shutting the car off for a couple of minutes and then restarting the car a few minutes later, the defroster fan came to life with the car & I was able to go to any mode perfectly, anytime untill it happened again last week and this week.

 

That happens to me intermittently when I use the defrost function. Had service check it out and they supposedly replaced something but it continues to happen...

 

Do you all have the 4-zone? I've had problems, but not like you describe with the 4-zone that doesn't seem to happen with the 2-zone. In the winter, I've had it a few times blow cold air out the front. And in the summer, I've had it blow hot air out the rear vents. I didn't even have my dealer look at it, since I knew that it could not be reproduced.

 

Ask MB software engineers.

 

yes this is the 4 zone standard in the E500