georgiabenz

I just replaced the ac compressor on my 2000 E320 with one that I had previously taken off a car my wife totaled. The replacement compressor was less than a year old and had been stored properly for 18 months. I also installed a new receiver dryer along with it. After installing the comp and r/d I pulled a vacuum on the system and let it sit for two hours with no bleed down or leaks. I recharged per spec and reset the ac fault codes, the ac worked perfectly with ice cold air for three weeks. Today I jumped in and took off but the ac didn't blow cold, only outside temp air. Yesterday it worked fine.

Here are the numbers:

The EC light is NOT on.
The AC Clutch will not engage.
The Low Pressure reading while running with ac on is 110 psi.
The High Pressure reading while running with ac on is 150 psi.
The only fault code is E 1419.

Here are the readings with car running in 84 degree heat:
1 100
2 84
3 107
4 107
5 103
6 181
7 07
8 91
9 30
10 4.5
11 2.8
12 4.2

Does anyone have an idea where to start troubleshooting?

Plutoe

The test don't mean a thing when the compressor is not running and making what ever pressure it can make--then all the sensor data will make sense.


Typically the compressor won't start because there is not enough refrigerant in the system!

fabbrisd1

I am not saying this is the case - since you did not mention outside ambient temperature - if the outside ambient is not sufficiently above aircon setting - like 5-6 degrees - then the system will not automatically kickin at startup - in this case you have to turn the climate contorl down - or simply turn climate control down to "lo" - to get the system to kick in

georgiabenz

Yes that is with the engine running. What do you make of the High and Low pressure readings that were obtained with ac gauges?

Chadzu

I had a similar issue with my clk. It turned out that the little control valve on the compressor stuck. This basically keeps the compressor from pumping. If you put gauges on both the high and low pressure sides, and they are about the same this may be your problem. This valve can be replaced if the compressor is otherwise healthy.

Artieboy

Hello.....I'm also having AC issues, my AC just stopped working.....trying to DIY to save a few dollars.

I have a 2000 E320 with approx 125K miles.

The error codes were:
B 1234 Sun Sensor
B 1235 Emissions Sensor
B 1419 Electromagnetic Clutch

Drove car for 30 to 50 miles with AC on max., but it keeps blowing warm air and codes have not reappeared.

One day later I noted the sensor readings as follows:
01 = 84
02 = 89
03 = 87
04 = 85
05 = 85
06 = 181
07 = 08
08 = 102

Are these reading within range, specifically #5, #6, and #7?

I'm hoping a safety feature or something in the AC system just shut off the electromagnetic clutch/compressor and it's not the AC compressor.

I've read online to check the voltage going to the electromagnetic clutch, I've also read online to test electromagnetic clutch with a direct 12 volt.

Can the electromagnetic clutch be replace by itself, or does the entire AC compressor need to be replaced?

Any assistance is greatly appreciated.

Thanks,

Art

kajtek1

Go to MBMedic for proper AC troubleshooting procedure.
Giving us only 1/2 of necessary data is waste of time on both sides.

Artieboy

kajtek1 thanks for pointing me in the right direction......I'm new to these forums.....

Artieboy

So I just rechecked for the error code, non have reappeared, they were B1234, B1235, and B1419 prior to clearing them.

The sensor data/values I just obtained are:
01 = 78
02 = 69
03 = 85
04 = 84
05 = 84
06 = 150
07 = 06
08 = 82
09 = 31
10 = 1.5
11 = 3.9
12 = 4.3
20 = 3.2
21 = 32
22 = 00
23 = 32
24 = 11.6
40 = 164
41 = 85
42 = 40
43 = 136

Is there other data which I need to obtain, if so, can you assist with procedures for obtaining this data?

Thanks again for any assistance......

Art

kajtek1

http://www.mercedesmedic.com/ac-air-...le-codes-list/
Follow the comments advise.

Plutoe

The only data point that makes sense is #7 refrig pressure--should be 15 to 17bar--you are either very low on refrigerant or your compressor can't make pressure---


PS: be watchful of spammers!!

Artieboy

Hello......the error codes/faults have not reappeared (B1234, B1235, B1419), and I noted the following sensor readings:

Early morning, engine cold:
01 = 67
02 = 66
03 = 73
04 = 71
05 = 71
06 = 80
07 = 5
08 = 69
09 = 27

Mid-day, engine cold:
01 = 121
02 = 91
03 = 123
04 = 120
05 = 105
06 = 157
07 = 9
08 = 107
09 = 27

Mid-day, engine running:
01 = 107
02 = 82
03 = 105
04 = 103
05 = 102
06 = 182
07 = 8
08 = 94
09 = 32

I also checked the low-side & high side at 90 degree temp:

Static Pressure, engine off - low side over 120, high side 115

Engine on, AC off - low side 103, high side 115

Engine on, AC on - low side 105, 125 high side

The AC clutch engages, and disengages when the EC is pressed.

Does this mean the AC compressor is bad, or maybe a valve on the compressor?

Trying to familiarize myself with how the AC works......thanks,

Art

kajtek1

Double check it as the errors are costly.
AC clutch on and compressor turning, car interior is hot and the climatronic is set to about 70F.
If you read low side 105 and high 125 psi, the compressor is kaput.
Working compressor should pump in high 200's or even 300's

Plutoe

The most important data point is 7 refrigerant pressure---fully charged systems should produce 15 bar. In your case you either are very low on refrig or you have a bad compressor---see a pro to determine the amount in system along with a pressure test to determine leaks---happy driving and watch out for spammers!

kajtek1

Yupp... good thing they ban them on benzworld.
At least 1 place when you can talk Mercedes without idiotic comments every 3rd reply

Plutoe

Sifting through all the HS what is the latest!

Chadzu

Sounds like the control valve on the compressor. You can either change the whole compressor out or change the control valve. Either way the compressor needs to come out.

Artieboy

Thanks all for your insights......it's a work in progress, will need to make the time to get the compressor out.....

Is there a way to test to see whether its the compressor control valve, or the compressor itself?

Thanks again,

Art

Artieboy

Any recommendations where to get the compressor or any other parts?

Art

kajtek1

Get the part # ,punch it on google and click "shopping"