'1999 E300D W210

Still trying to get my AC working.

EC light is on...won't go out. I checked the codes and found that the evaporative temp sensor was defective. I've replaced it...but no joy.

Ran diagnostics again..... and the refrigerant pressure was showing only 1 bar so today I bought a DIY fill hose and a can of R134a. The hose has a gauge which showed right on the border between OK and needing a fill. One can raised the pressure to over the green part of the gauge an half way into the "caution'" area but with the compressor still off....it didn't kick in. The gauge and the on board diagnostics now shows 3 bar...

The compressor still doesn't come on.

Fuse....?? or is there some kind of "reset" ??

What else can I check and fix myself.


Warren C.

Did you reset the codes? Is the EC lamp now off?

Don't think so ???

How do I reset the codes?

EC lamp still on.

WC

Check for codes again, when finished press and hold both auto buttons for 3-5 seconds to erase, then turn ign off.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Thanks,

Checked DTC codes ....I had several codes stored

b1-231 - coolant temp sensor problem (??)
b1-234 - sun sensor on the dash (not critical)
b1-241 - low refrigerant
b1-416 - coolant circulation pump problem (??)- circulates coolant after engine is off.

(FYI and others who may read this thread in the future, I found this link very informative. ) http://www.eclassbenz.com/node/27

I then erased the codes per your instructions....and HOORAY !!!! My EC light now goes off. Ran the engine at idle for about 3-4 minutes. When I check for trouble codes again....not getting any?

Reading my actual values I'm now getting numbers in positions 1-8 that look normal except for #7 which now reads "01" (bar)....which, I'm sure must be low.

Is this sensor reading low side or high side pressure?

How many "bar" should it read to be in spec? (I've seen numbers reported all over the map ...and as high as up in the teens...???)

I've got at least two more cans available.


Warren C.

It only holds like ~2.1 lbs total, so slowwww down.

Let Matt or someone else help you determine if it actually IS charged already and a sensor or switch is bad.

Pressure is variable.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

EC light goes off.

Code #7 pressure up to 04 at idle, but ambient temp only 70 degrees.
Monitoring pressure while driving it increases to as high as 12m sitting in grocery store parking lot.....but evap temp stays warm at about 71.

I'm not hearing the compressor click ON...but if I press the EC button so that the light comes on the pressure slowly drops ....so seems something is working ..(??)).

1 Error code:
eb1-416

WC

There is no single correct high-side pressure. It depends on the conditions of the test.

There are pressure charts in the service manual, as is the case for about anything. These have specific testing parameters, and even then will only let you make an educated guess as to the actual refrigerant level in the system. There is only one way to be sure of the refrigerant level, and that is to evacuate the system and replace the refrigerant with the correct quantity.

There is one additional thing that should now be asked. Did you purge the hose of air before you added the first can of refrigerant? If not, you would have shot that bit of air into the system. Air in your system is a very bad thing and can lead to excessive head pressure without actual cooling capacity.

Seeing 12 bar without good cooling would make me suspect air in the circuit unless I knew for a fact that this was not possible. Too much oil in the system can cause similar problems.

Finally, be SURE to NEVER add leak sealers to your system. No o-ring conditioners either. You don't need them and they can cause a lot of damage. Yes, I know that the big-box stores only seem to carry stuff with additives, but you can find pure 134a and PAG-46 oil without looking very hard at all. The only thing that is allowed in the system other than 134a and PAG-46 compressor oil is UV dye.