Must Fix! Please help (Climate Control) - PeachParts Mercedes-Benz Forum

TROVERMAN · #1 02-24-2004, 04:44 PM

Have posted this before, searched this site, and would like some assistance here...the car is the 1995 E320 Wagon, low miles, with auto climate control. It has the temp wheel, then the 5 or six pushbuttons for air distribution, including the EC (Economy) setting, and then the 3 fan speeds buttons. (Hi, Lo, Auto)

Problem is this. After having a dead battery (may be a total coincidence), the previously perfectly functioning climate control now only blows air from the defrost (windshield) vents and the 2 outer dash vents, like it is stuck in the defrost position. In addition, the recirculating / dust filter no longer functions. The switch lights up, but airflow doesn't change.

Regardless of what position the pushbuttons are in, airflow does not change.

Fan control still works fine, as does the temperature setting. The fan will automatically slow down when the temp is reached. Cannot tell if the a/c system is working because it is too cold here for that. It does click on under the hood, though.

I think the problem must be vacuum related, dealing with the air box control shutters, or something. I could really use some help here.

Thanks

engatwork · #2 02-24-2004, 07:32 PM

Sounds to me like the pushbutton control unit. See if you can find a good one to try in there. Did you have to jump start it? It may have done some damage

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HGV · #3 02-24-2004, 07:33 PM

When the battery went out on my 95 e320 wagon, it leaked battery acid on the vacuum lines located behind the battery area and messed up the climate control system. The acid cracked the vacuum lines and things began to do strange things. Hope this helps.

Henry

TROVERMAN · #4 02-26-2004, 01:10 PM

Thanks, guys. Here is the situation. (Won't be able to update again until Monday or Tuesday) Yesterday I took the climate unit out, and took it apart. Everything seemed good! No burnt out areas or loose solder points. Plus, everything seems to work accept air distribution. If I press "0", it shuts off, and all of the other buttons turn it on. Defrost automatically blows max heat. The A/C compressor comes on when anything except EC is used. Like I said, the temp control still works, as does fan speed. And it all lights up correctly. Its a 95 with low miles, so not much use. I don't think this is it.

About the vacuum lines, though. When the black pushbutton unit is out of the dash, there is a visible white vacuum control unit, with a red vac line on one end and on the other is a metal lever. I took the vac line off and with the CCU plugged in and the car on (and the CC on) there was no vaccuum, no matter how I adjusted the temp or setting. When the CC was on and I manually moved the lever I think it either turned on recirc or made heat blow to the floor. Anyways, it doesn;t work right. Where can this line be traced to?

About acid leaking: When my original batt died, the CC had been working perfect the day before. After jumping it, it never worked right. (In the state it is in now) However, I did switch batteries (to a used EXIDE which was in one of my other vehicles) and this cooked the Exide, leaking acid all over the batt box and below. I neutralized with baking soda when I discovered this, but you never know. I don't think the original ever leaked. In fact, after the Exide boiled over, I charged the original battery and have reused it without trouble ever since. I seemed a little low on electrolyte, so I topped with water. The thing is, the CC stopped working correctly I think when the original batt which didn't leak was still in, so I don;t know about the vac leak theory. (Although I think the whole prob is caused by lac of vac.) I will check, though, so thanks all. By the way, for anyone with a 95 wag, do you hear a hissing sound of vac near your brake master cylinder? There are a few vac lines over there and I hear a disitnct hissing. Don't know if this is normal or not.