PeachParts Mercedes-Benz Forum

PeachParts Mercedes-Benz Forum (http://www.peachparts.com/shopforum/)
-   Tech Help (http://www.peachparts.com/shopforum/tech-help/)
-   -   W211 AC Wiring (http://www.peachparts.com/shopforum/tech-help/369536-w211-ac-wiring.html)

sredwine 06-23-2015 03:09 PM

W211 AC Wiring
 
I am trying to troubleshoot my car's AC (it's hot!). It's a 2005 E320 wagon with the two-zone system. The controller seems to be OK-but the compressor never comes on. The charge pressures seem normal (static low-pressure measured 100psi on a 98 degree day). The diagnostic computer says the pressure is 10 bar-way higher than it actually is. Can anybody give me the static readings I should get off the refrigerant temp/pressure sensor (two sensors in one housing)? Also, where is the line that activates the valve in the compressor? None of the diagrams I got from Star Info or WIS spell this out. Lots of block diagrams, but I want to know what wire to probe!

JimFreeh 06-23-2015 06:52 PM

Quote:

Originally Posted by sredwine (Post 3490377)
I am trying to troubleshoot my car's AC (it's hot!). It's a 2005 E320 wagon with the two-zone system. The controller seems to be OK-but the compressor never comes on. The charge pressures seem normal (static low-pressure measured 100psi on a 98 degree day). The diagnostic computer says the pressure is 10 bar-way higher than it actually is. Can anybody give me the static readings I should get off the refrigerant temp/pressure sensor (two sensors in one housing)? Also, where is the line that activates the valve in the compressor? None of the diagrams I got from Star Info or WIS spell this out. Lots of block diagrams, but I want to know what wire to probe!

The electrical line to the compressor is connected next to the one of the pressure lines at the top of the compressor. I *think* it's not a simple 12V on or off, it may be a pulsed DC signal to vary the swash plate. As you noted, the compressor is engaged all the time, no traditional clutch.

I borrowed an SDS computer which gives all the A/C parameters, it was essential to do the diagnostics on the system.

Refill is 2lbs, 2 oz. I was also seeing some high pressure in the system, more than I was accustomed to, might have been due to the 95 degrees and high humidity...
Static was around 120 on the low side, 140 on the high side at rest.


Jim

Jim

sredwine 06-23-2015 08:45 PM

Quote:

Originally Posted by JimFreeh (Post 3490442)
The electrical line to the compressor is connected next to the one of the pressure lines at the top of the compressor. I *think* it's not a simple 12V on or off, it may be a pulsed DC signal to vary the swash plate. As you noted, the compressor is engaged all the time, no traditional clutch.

I borrowed an SDS computer which gives all the A/C parameters, it was essential to do the diagnostics on the system.

Refill is 2lbs, 2 oz. I was also seeing some high pressure in the system, more than I was accustomed to, might have been due to the 95 degrees and high humidity...
Static was around 120 on the low side, 140 on the high side at rest.


Jim

Jim

Thanks for the prompt and meaningful reply, Jim. Was your compressor coming on? what was your fix?

JimFreeh 06-25-2015 06:33 AM

Quote:

Originally Posted by sredwine (Post 3490467)
Thanks for the prompt and meaningful reply, Jim. Was your compressor coming on? what was your fix?


http://www.peachparts.com/shopforum/tech-help/369407-w211-cdi-refrigerant-charge-amount.html

Jim


All times are GMT -4. The time now is 10:00 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website