[saintz]

2002 W210 E55

AC doesn't blow cold.

Sensor readings - after 3 minutes (after 10 minutes)
1: 75 (80)
2: 75 (76)
3: 73 (89)
4: 73 (93)
5: 73 (76)
6: 163 (182)
7: 00 (01)
8: 71 (75)

DCT Codes
B1226 - In-car temperature sensor (B10/4)
B1416 - Coolant circulation pump (M13)
B1422 - Series interface (K1) connection to instrument cluster (A1)

I reset the codes and now I have no codes being thrown. I think B1416 is only heating related, so don't care about that for now.

The sensor 7 (compressor pressure) was at 0 and then finally came up to 1 after I filled with r134a until the gauge said full. Do I need more refrigerant? I'm afraid to fill past "full" into the "alert" area of the gauge, but the code seems to indicate the refrigerant is low (or is the compressor just not running?).

Any help appreciated, thanks

 

[saintz]

The AC compressor clutch does not appear to be spinning. The belt is spinning, but even with the AC on "Lo" the center of the pulley does not spin, it just sits. I assume this means the compressor is not coming on, not sure if that means it's dead or if it is shut off due to low refrigerant.

 

[Tubers]

It appears that you have a leak. From your numbers, 7 indicates how much pressure in bars you have on the high side.

7: 00 (01)

Yours indicates no pressure. Even with the system off it should still read 6 or 7.

I would get refrigerant with dye in it and see if you can figure out where the leak is.

 

[fabbrisd1]

My suggestion...

One thing that I see - the evap temp sensor reading is way whacked out - and as a result that can prevent the compressor from coming on. If the compressor gets locked out - then you will not get a pressure reading.

The Behr OE sensor is like $35 - I do not recommend the China sensor which is about $20.

Replacement is fairly straightforward DIY - there should be a pictorial in the stickies or with forum search.

Once the temp sensor is replaced - if the compressor is still good - then it "should" kick in if there is sufficient refrigerant pressure.

If it was me - I would replace sensor 1st - then chase the rest - the rest might be system leak or blown compressor - but if there is a evap temp sensor failure - you can't diagnose the rest until that sensor is replaced/good.

 

[Kajtek1]

Sensor or not, the system will not work empty.
Do what dlafever says and go from there.
I experienced that computer has default mode for evaporator sensor.
On one car it was constantly showing over 150F, yet system worked just fine.

 

[saintz]

It appears that you have a leak. From your numbers, 7 indicates how much pressure in bars you have on the high side.

7: 00 (01)

Yours indicates no pressure. Even with the system off it should still read 6 or 7.

I would get refrigerant with dye in it and see if you can figure out where the leak is.

The compressor doesn't seem to be running, so that seems to be the issue with the high pressure side. At this point, I don't think I can add anymore refrigerant to the low side unless I bleed it first. I'm assuming I can't add refrigerant to the high side.

One thing that I see - the evap temp sensor reading is way whacked out - and as a result that can prevent the compressor from coming on. If the compressor gets locked out - then you will not get a pressure reading.

The Behr OE sensor is like $35 - I do not recommend the China sensor which is about $20.

Replacement is fairly straightforward DIY - there should be a pictorial in the stickies or with forum search.

Once the temp sensor is replaced - if the compressor is still good - then it "should" kick in if there is sufficient refrigerant pressure.

If it was me - I would replace sensor 1st - then chase the rest - the rest might be system leak or blown compressor - but if there is a evap temp sensor failure - you can't diagnose the rest until that sensor is replaced/good.

The Evap reading seems to be reading about ambient (76*). What should it be? About 10* higher?

Sensor or not, the system will not work empty.
Do what dlafever says and go from there.
I experienced that computer has default mode for evaporator sensor.
On one car it was constantly showing over 150F, yet system worked just fine.

The low pressure side is full (or at least the gauge on my can says it's full). The high pressure side is empty, but the only place I can fill the system (low side) is already full. Unless I need to somehow fill the high pressure side.

 

[Kajtek1]

You stop charging the system because the gauge show can pressure.
Car AC is empty period and compressor will not start till you give it initial charge.

 

[Yacht Master]

You may have a huge leak, if in fact you "charged" the system with one of those craptastic cans with a plastic gage on it. Your #7 should read at least 2-3 bar.
You have some very wrong ideas about high side VS low side, they are connected, static engine not running the pressure (high & low) will be the same.
I think your best course of action is to seek a professional AC tech with MB experience.
To recap, if you put one can (one pound) in the system, that should be sufficient to allow the compressor to engage.

No engagement means, system is not holding sufficient pressure (your #7 at 0) or the compressor clutch is inop.

Note to all using a can of R134a with plastic gage, 99.9% of those have a sealer in the mix, not the best thing for your system, many AC shops will not recover or recharge a system with this R134a+sealer in it. Second the gauge is almost useless to charge our system correctly, we have a variable displacement compressor and because of this we have pressures that fluctuate from 6-20 bar.