Jakpro1

Only takes a minute or so and is TOTALLY harmless. Just a way to read settings inside the car.

I am trying to diagnose this friggin ac as it's never really worked correctly and I died a thousand deaths in the 100degree heat today.

If you have nice cold ac and are in a place where you can start your car for about 60 secs or so. Do this for me.

With the car running for about 60 secs, set your temps for both sides on 72 and then hold down the "AC Off/Rest" button for 5 secs.....or basically until you see the number "1" come up on the left side instead of your temp.

To the right of the number 1 will be another number. Example 1-------then 32. Can you jot down the numbers you get on 1-8 for me. Use the up and down temp buttons on the left side to move up and down from 1-8.

Really looking for #7 value as that is the amount of AC R134 in your system. Mine says around 14.

By the way, here is what each number means so you can know what you are looking at.

1 in-car temp
2 temp outside
3 heater core temp, left
4 heater core temp, right
5 evaporator core temp
6 engine coolant temp
7 refrigerant pressure (in bars)
8 refrigerant temp

To return the car back to normal, just hold down the "AC Off/Rest" button or turn the car off and remove the key.

Thanks so much you guys. Really will help to know what pressure healthy AC units are under.

Thanks again!!



Here is what I got today to compare with yours.

1---31
2---31
3---53
4---37
5---27
6---94
7---14
8---68

blackbenzz

#7 fluctuates during driving. It's the freon pressure.

izzyz28

Here's what I just got. It's only 79 degrees outside, but the A/C was running. I will say right now that with an evaporator core temp of 27c, you have an issue for sure.

1 - 24
2 - 24
3 - 28
4 - 26
5 - 03
6 - 46
7 - 09
8 - 36

mikey33

My AC gets ice cold in about 2 minutes in 128 degree interior temperature. I will try the test and post results.

mikey33

Here are the readings with an outside temp of 102.

00 - 27
1 - 28
2 - 28
3 - 43
4 - 42
5 - 01
6 - 92
7 - 13
8 - 48

mikey33

The only drastic difference I see between all of our numbers is reading #5.

Benz-O-Rama

Jim, what stands out to me is the difference in temp between the left and right heater cores. Have you looked at this?

https://mbworld.org/forums/e-class-w...rol-valve.html

Not sure if it's the fix you need, but worth a looksie.

Jakpro1

A million times over..... thanks to all you guys!!

I was just thinking I was having a leak somewhere but my AC pressure seems fine.

This was just what I needed.

Time to start replacing smaller stuff and praying it is not the evaporator. Whole dash gotta come out for that. Without warranty, ugh that would be rough.

shardul

iTrader: (1)

07 - 09 when the outside temp was 79

blackbenzz

Hmm it looks like the E55 readouts might be in Celsius whereas mine is in Farenheit

shardul

iTrader: (1)

yes e55 engine coolant temp value 6 is in centigrade scale

£ C43 £ AMG £

W211's dont really seem to suffer from evaporator problems.

Most problems are with the electronic thermostat on the AC compressor unit.

Does the AC work sometimes when you are moving at high speed?
Does it work when you first turn on the car but then the problem returns after a stop and start run or does it not work at all?

Jakpro1

Well an update for ya. Looks like this one could be cut and dry.

Got the car apart and put some dye in. Looks like my compressor is giving up the ghost. Dye all over the bottom of the compressor unit.

I know there are kits to just rebuild the front but I think it is best to swap it out totally.

Also replacing drier. Here's hoping for ice cold AC for the first *&(&*(in time in the cars history.

I can imagine the storys on the other car forums. This really creepy looking super sweaty Italian looking guy killed me in his E55. He looked like he was gonna hyperventilate in there.