Mercedes Air Conditioner

[Bengt_Phorqs]

My bride has a 1999 Mercedes Benz C280 with a very peculiar issue.  A month or so back the a/c just quit working on the way home.  The next time she got in and started the car the a/c worked.  Then it would quit after five miles or so.  If she turned the motor off then restarted the car, the a/c would work again.

On the cooler days we had last week the a/c would work all the way home but on days where the temp is over 95F it goes to off again/on again thing.  I suspect there might be a circuit breaker in the M-B a/c circuitry that is tripping off then re-sets when the ignition is turned off.  I don't know a thing about those cars and just wondered if anyone of the technical savants on this forum could lend me an idea or two.  Free beer to anyone who can come over and fix it! [smiley=1drink.gif]

[montmil]

Did Theresa ever try my idea of dialing back the thermostat a tiny bit? Like the condenser is freezing up as on an old Chevy we had. Blows cold then not so cold...   Monte

[Bob_Roller]

There's a diagnostic electrical connector for the system, without getting the fault code(s), you're going to be chasing your tail on this one .

So it looks like you need to find someone with the proper code reading device, I don't know if the diagnostic tools that some chain type auto parts stores rent out, for a hefty deposit, would be able to decipher the info or not .

[Bengt_Phorqs]

Monte, changing the thermostat doesn't seem to have any effect.  I've experienced that before with American cars and it does take a little time for it to warm up again.  This happens when she turns the car off, then on again and she's good for another five miles.

Bob, I think you are right in that the fault code needs to be diagnosed.  We're not about to take it to the local robber baron M-B dealer so we'll try to find a local shop that works on these things.

Thanks for the suggestions!  

[Justin B.]

I have an OBDII and CAN BUS scanner but I don't know if the codes would be stored in the PCM...  You are welcome to swing by, hook it up, and see if it has anything useful to say...

[Motu]

I don't think the air con is controlled by the computer on a C class,so a scan is not going to tell you much.It's most likely just low on gas - get it recharged and see how it goes.There could be a leak too....if they suspect a leak,then a dye can be put in too.

[wa1udg]

Some folks think their auto AC is broken when it's the valve for the heater not turning off in a "autoclimate control system.  DOes sound like low low charge problem to me though. Most systems have a low pressure shutoff switch because the when the gas leaks out so goes the compressor lubricant as well.  

[Paper]

I met this guy yesterday and he's one of those guys that makes me wish I had a MB just so I could have him service it..

http://www.brooklyn300.com/