TRJNHRZ

Please help! The A/C in my '99 E430 seems to work whenever it feels like it. It works fine for 3-4 days, and then all of a sudden it'll blow hot air. The very next day, it'll blow cold air.. and then a few days later it'll blow hot air again. Anyone have an idea of what the problem is? I've "heard" that it either needs refrigerant or a malfunctioned compressor. Please help, California heat in summer is unbearable.. even for short periods of time!

Thx!

MARK CUMMINS

I Would replace the A/C Evap Temp sensor..Its located in the A/C Evap...remove the left under dash to replace it..its located in the center of the housing
a 10min job

I Have seen SEVERAL of the sensors go bad ..with the same complaint as you have posted..

Also do a search on the W210 a/c controls for a read out ..Just to be sure..You will be able to read the values on the A/C control unit screen for the sensor It will be out of spec!

TRJNHRZ

Mark,

Thanks for the info! Not sure I'm following you on what you mean for doing a search on the A/C controls. Can you elaborate?

Thx!

yugger

Strange thing happened to me a couple times this weekend. It was in the upper 90s and I was driving along with the A/C on when all of a sudden, hot air started coming out of the driver's side and foot vent. I turned the climate control on and off a couple times, but that didn't help. Then stopped for about 30 mins, got back into the car and everything worked fine again. Later in the weekend, hot air started coming out of the passenger side vent. Turned off the climate control for a bit, turned it back on, and all was ok again. Seems to be working fine again...for now.

Strange that it's only 1 vent at a time. Does anyone have any ideas on this?

BTW, it's a '97 E420

Thanks in advance!

yugger

... the other vents that weren't blowing hot air worked normally, blowing ice cold air. This seemed to make the whole climate control system go nuts.

why_not

Did u solve the problem ??
My car did the same thing today..

Its ok again now..
Did a diag test..

Evap sensor is "2" right now.. is that normal ?..
Pressure: 13bar


Right now i have several diag codes..
Evap sensor
Incar temop
heater core temp
Refrig temp
Refrig pressure
sun sensor
and
serious IF to Instrument cluster

Can these be old codes from before i got the A/C refilled ?
If yes..Is there any way to reset these codes ?


Thanks
/kim

HTBenz

How do you run the test on the system?

why_not

http://www.continentalimports.com/ser_ic40142.html

Via the guide above..
/kim

fast_car

My wife 1999 E320 just start to have the same problem as stated above thread, any one can advise where to start the trouble shoot

Thanks

why_not

When the error is there..
try to get the readouts from the AC sensors..

i havent been able to get them whuile the errors are there..
/kim