[Ryantrav]

My girlfriend has no heat in her 04, c230k. All the fans speeds work. I have heat going to and coming from the heater core and ive checked fuses relating to heat. I let the car idle trying to warm up and felt the ac compressor turning on and off without the ac or defrosters on. I felt the lines going to the evaporator core and they were cold and had condensation on them so I’m stumped. Looking through fuse box diagrams stand I can’t seem to find a ac clutch relay on any of them. If anyone’s had an issue like this before let me know. Also the heater core is not by passed

 

[db3024]

My girlfriend has no heat in her 04, c230k. All the fans speeds work. I have heat going to and coming from the heater core and ive checked fuses relating to heat. I let the car idle trying to warm up and felt the ac compressor turning on and off without the ac or defrosters on. I felt the lines going to the evaporator core and they were cold and had condensation on them so I’m stumped. Looking through fuse box diagrams stand I can’t seem to find a ac clutch relay on any of them. If anyone’s had an issue like this before let me know. Also the heater core is not by passed

Few things to check;

Faulty or old coolant temperature sensor. About 15-20 bucks from the dealership. Not sure if they raised the price.

Wrong antifreeze(use Mercedes/or European specific.. usually a blue color). I had no idea how this made a difference until I was informed by a tech. If not currently using Mercedes specific coolant, flush the system with new approved coolant. Burp the system.

Ensure that there is no issues/ sticking from the thermostat. They tend to go bad after 100,000 miles and the housing/gasket is prone to causing leaks.

Ensure high and low pressure a/c ports aren't leaking from the valve stem.

Hope this may help

 

[rudeney]

Welcome to the forum @Ryantrav - please take a moment to read the information on the links below. It explains how to use the forums and update your user profile so that your car's details and your location appear on each post below your avatar. This is good information for others to know when trying to help. It also has good information about how the forums are organized and how to use the search feature:

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Complete your profile.

You need to pull codes from the ACC system.
A generic $25 OBDII scanner won't do this. There are some fairly affordable ($100 or so) tools that will do this such as the Autel DiagLink, iCarsoft (i980, MB-II v 2.0 or v3.0) and the Foxwell n510 Elite. There may be others, too. Just look for ones advertised as reading "all systems" and for Mercedes-Benz. This way, you can read and reset codes for yourself without paying the shop. There are many people in the forums that, given the proper codes, can give you some direction.