Em Bee Lover

Live in upper midwest. Don't run a/c compressor from probably mid-October to May. Fired it up and only tepid/cool air blowing. Settings are good; it switches from "max a/c" to normal on COMMAND. Blew cold when last used. It's a 2007.

Simple a/c shop recharge or have others experienced bigger/other causes.

Thanks.

ima55r2

The seals on the freon lines could dry up, crack, and then leak if the A/C is not fired up on a frequent basis. I think there is an easy test for leaks with a meter that sounds when detecting the gas.

Em Bee Lover

Looking for guidance prior to going to mech.

Am becoming more and more cynical, as SA's say one thing, I spend hundreds and things are still not fixed. Then asked to spend more.

Knowledge is power? Yep. Thanks for the insight/advice.

Diesel Benz

Not a problem on this car, for a long time now MBs have had continuously running (variable displacement) compressors. They run all the time, not even a clutch for winter, they just run at a very low percentage from max power (something like 2 to 3%). Seals too are different today.

Makes sense. I'm not aware of typical AC issues on a W221, any car could have a leak at some point.

bear1947

Driving to Florida on vacation. A/C worked fine when leaving, then stopped working no notice. Long story short, Low pressure line starts to breakup internally spewing pieces into compressor taking it out. Mechanic said there is a TB on this problem. My is a 2007 with 59K on it. $1800.00 bill to fix from independent. God only knows what a stealer would have charged.

Em Bee Lover

Did you also have the mech replace the line, so a couple years hence the same thing doesn't happen? I think I might be experiencing what you did. I am just curious if line replacement was part of the $1800. Thanks.

NuMBS500er

will the MB extended warranty cover this?

bear1947

Compressor was $870, drier was $180 and low pressure line was $170. Labor was $520. Reasonable compared to a stealer. Nice indie in Jupiter Fl. A limey named Pete at Eurostar Auto Service. Don't have extended warranty

Em Bee Lover

Long shot. Anyone had AC blowin' cold and working okay, then had telematics updated and AC and signals appear okay, but blows only "vent" or outside air, not cold?

Saw snippet of this in another forum and now cannot find.

The scenario I list is how mine went down. Freon and all other is fine. Is there a control module or similar for AC? Anything that could tie to this?

Thanks.

NuMBS500er

I had the similar problem as Em Bee Lover. I just got the car back from dealer, they replaced the fan unit, now it's fine. The repair was covered under my warranty.

T0ked

You are a brave, brave, man. When I can no longer get an extended warranty on this car is when I sell it.

Em Bee Lover

[quote=Em Bee Lover;4694278]Long shot. Anyone had AC blowin' cold and working okay, then had telematics updated and AC and signals appear okay, but blows only "vent" or outside air, not cold?

Saw snippet of this in another forum and now cannot find.

The scenario I list is how mine went down. Freon and all other is fine. Is there a control module or similar for AC? Anything that could tie to this?

quote]

Just returned from MB dlr. Indie computer diagnostic showed compressor fault. Replaced with MB compressor and drier, not aftermarket. Still no ac.

Relented and went to MB dlr. Diagnostic there also showed fault in compressor. But, their software could dig deeper. Turns out the SAM and compressor needed to be reprogrammed, as the SAM was "seeing" a compressor w/ mechanical clutch, when newer MB (compressor is actually a Japanese Denso brand...) compressor has eletric. Programmed SAM to "see" electric clutch compressor and the ac works perfectly.

Take away? If ac quits working out of the blue and you've had a telematics update, check the programming before replacing hardware. My not getting the dlr. diagnostic made me spend hours and $1000, it appears, needlessly.

Even if no Telematics update, the software glitches and sophistication of the car can be touchy.