Navish

So just got a another problem in the e320, for some reason the ac is blowing hot air even though its on the coldest setting possible. Another thing is the the (AC Off) switch stays lit red the whole time it wont turn off. Also there is perfect freon in it, cant even add more to it.

- Is there a way to reset the whole computer (everything in the car)?
- Possible only resetting AC?

Yea would greatly appreciate any help at the moment, sucks being in 80° weather with no AC......

Plutoe

When you purchased a W211 you lost all the self AC diagnostics of the W210---you need to find a good AC guy with MB diagnostics to locate your problems.

FYI The AC off switch always on means that your compressor is not working because there are issues with the system that will cause damage!!

Navish

Called local Mercedes service shop they told me it would cost me a fortune to get it fixed. Later found out that the only way to get "AC Off" light to go away is to read and clear the fault code. But was also told many places don't have the right tool.

So is there any cheap generic tool to read and clear a fault code, don't wanna waste too much money. Or anyone around Houston,TX that can do this for a good price.

Plutoe

You had to drive and MB----use the yellow pages to find a shop with DAS Xentry diagnostic tool



Update: Focus on the so called european car shops or used car dealers specializing in european cars!!

Navish

Looked all day today haven't found anyone yet around Houston,TX (77479). Its becoming a big problem because the weather is burning hot......

Plutoe

An afterthought---you know you have to pay someone for the diagnosis and then someone to do the repair---why not use the dealer for the diagnosis, but this time you don't pay them until they clear the faults and you get a print out of the AC control module fault list---not the quick test but the AC module fault list!!

Once you know what's wrong any putz at any AC shop can replace the component!!

Navish

The local Mercedes dealership is asking $150 only for the diagnosis.

Navish

I ended up getting the problem fixed for free from a friend of mine, what had happened was that the compressor turned itself of cause of low freon pressure, so a fault code had to cleared for the HVAC system. Once that was done the compressor kicked back on and started to take freon again.

FYI: no special Star system was required, my friend used his Autel MD802 that has the ablilty to read and clear any fault codes for all electronic module. He recently got it from amazon for $350 rather than the retail of $780, very handy tool to have.

Plutoe

That's great when are you going to get one!!

Navish

UPDATE: The light came back, called my friend again told me its most likely a small leak since it took awhile for the freon to leak out.

Are there any products that can small stops leaks?

Plutoe

Well the good news is that it sounds like every six days you will have to call your friend to tell you what we told you six day ago-----you have a leak---you do know what the definition of a leak is??---it's not a perpetual motion leak where it leaks out then by some cosmic design it refills itself only to leak again in six days----does your friend have a sister, I think I also have a leak!!

Navish

Going to find some way to fix the leak and get the fault code removed again.

FYI: He had a sister........

Navish

Went back today to the car mechanic, and told him that it screwed up again. He was nice enough to use some huge machine to recover,vacuum, and recharge freon with dye in it, but this time there was another problem the pressure on the high side was above 420+ it concerning both of us. He told me there is a blockage most likely the AC expansion valve s that is causing the pressure buildup.

Where is the AC expansion valve located, and could there be any other possible problems?

Plutoe

follow the pipes to the engine firewall where they go into the evaporator---

if your friend aka AC mechanic is asking that question---the other possible problem is the mechanic is really not an AC mechanic but a tea seller!!

Navish

Finally had time to mess around with the car and locate the expansion valve, but am having trouble getting the 2 nuts loose from the valve. I cant seem to find a tool thats gonna do the job, have tried every tool from homedepot/autozone.