AC not working.
heres my problem- AC is not working
i have the analog contoller on coldest setting for both zones and it blows hot air.my troubleshooting:
- checked the fuse (41 and i believe 52 or something like that for the AC related)
-checked the freon level. released some and the recharged back to specification (thought of being overcharged and causing the sensor to 'trip')
-googled for the past 2~3 weeks
-searched everywhere on this forum
-couldnt find "duovalve" on the car nor the forum or google.
-no clicking sounds.
-i learned that there is no clutch for the AC compressor.
-looked at all possible PDF files in regards of AC related and came to a dead end.
any help would do.
Thanks in advance!
are your fans running at high speeds?
does it blow hot only at idle but cold in motion?
those were my symptons

128k miles on the clock. its an 02 c240 sedan(forgot to mention that lol)
i actually wanna look at the mixing valves. but the thing is, last night i sat in the car in the silent playing with the switches and such and i can hear everything moving around without a problem (vent location, temp, recirc, etc) no click no nothing.
im really hoping its not the compressor.
oh and another note...when i checked the freon level, the low was spiking and high was "low"...that usualy means expansion valve but something else tells me its not. gauge doesnt get effected with engine on or off.
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The compressors are different for different model years, so yours may be more or less money.
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OP - I will see if I have electrical schematic - not hopeful & my filing sucks.
6yrs 42k miles.
One day it just stop blowing cold air, only warm air.
It was the AC condensor on my car.
Cost me $1200 at the dealer.
I did the same as you, and searched every thread here to find a DIY.
Not to hijack your thread but here's my issue:
My car started blowing not awfully cold air, just ok, it seems that it was working and everytime I added freon it seems that it was working a little better. One day it just quit working at all and now the EC red light is constantly on (and of course, blowing warm air).
The guy at a local oil change shop told me that the problem was the compressor... ughhh. He said that the pressure going out was less than going in or something (maybe it was backwards)... who knows... he took $49.99 from me and did nothing.
Other than another over $1k of repairs what should I do? No DIY for AC repairs here?
Helpy, helpy please
i still didnt figure this out yet.
can someone post a diagram or know how to bypass the pressure/temp sensor switch(jumping a wire or 2)? i want to see if thats being the culprit.
But thanks for all your helps!!
But thanks for all your helps!!

In some countries you are not allowed to vent R134a to atmosphere. It's ozone friendly as opposed to R12 so I don't see the issue.
Good luck!
Thank god, this isn't my DD as its been high 90's to low 100's in NJ.



