Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 05-22-2011, 11:08 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
77 240d AC Wiring Problem

Here is my homemade schematic, I do not have enough power to kick in the compressor. I have three wires running all go from the box that houses the resistors on to the Receiver/Dryer. The Red one on my drawing is Hot, it light's the test light bright, the pink wire has power but is weak, it lights the test light but nothing like the Red wire, reduced electricity. The other wire has no charge. I have traced these three wires back to the box that holds the three resistors. No breaks found. When I put the test light on the pink wirs I do hear chatter in Resistor A. I swithced it out with another resistor from a 1980 parts car to no avail. Thought maybe the pressure switch was bad and swithed it out as well, still nothing.

The point being AC will not come on, seems there is not enough electricity going through the pink wire to kick compressor on, assuming the pink wire is the problem. I did jump hot wire from the battery to the the 'Junction' compressor kicks in and aux fan comes on. Its getting Hot in Texas and I need you guy's to chime in Please...

__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #2  
Old 05-23-2011, 11:23 AM
meltedpanda's Avatar
Certified Benzaholic
 
Join Date: Mar 2003
Location: Central Ky
Posts: 6,044
sure your grounds are clean and secure??
Even if you are hook up a direct temporary ground and see what happens
__________________
Ron
99 E320 THE Queen Mary
62 220b - Dolly - Finally my Finny!
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
07 Lexus RX 350 - Lexi
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
Reply With Quote
  #3  
Old 05-24-2011, 12:21 AM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
bump
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #4  
Old 05-24-2011, 09:18 AM
Registered User
 
Join Date: Jun 2005
Location: Chicagoland
Posts: 1,240
Your picture is hard to understand, but why do you have the resistors in-line with the compressor? The AC compressor only needs +12 volts to kick in the clutch - aren't those the resistors for the cabin fan?
Reply With Quote
  #5  
Old 05-24-2011, 11:14 AM
meltedpanda's Avatar
Certified Benzaholic
 
Join Date: Mar 2003
Location: Central Ky
Posts: 6,044
did you try the separate ground, hard to help unless you try the things or comment on things suggested- just saying
__________________
Ron
99 E320 THE Queen Mary
62 220b - Dolly - Finally my Finny!
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
07 Lexus RX 350 - Lexi
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
Reply With Quote
  #6  
Old 05-24-2011, 01:30 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
Quote:
Originally Posted by meltedpanda View Post
did you try the separate ground, hard to help unless you try the things or comment on things suggested- just saying
Yes I did seperate all of the grounds and tested them individually and then as a whole all ground points are good.
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #7  
Old 05-24-2011, 01:39 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
[QUOTE=thorsen;2723282]Your picture is hard to understand, but why do you have the resistors in-line with the compressor? The AC compressor only needs +12 volts to kick in the clutch - aren't those the resistors for the cabin fan?[/QUOTE

I put the pic of the resistors on the schematic to show that the resistor labled A clatters when I touch the test light to the hot wire that is showing lesser voltage, by not lighting my test light up fully. The black line running from the left to the right and up to the resistor box only passes under the box to another junction of wires between the firewall and the resistor box, from there it splits and comes back to resistor A, B and C. Sorry for the pic quality if it will help I will try and make it better but hard to do when using (Paint / bitmap)
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #8  
Old 05-24-2011, 03:08 PM
meltedpanda's Avatar
Certified Benzaholic
 
Join Date: Mar 2003
Location: Central Ky
Posts: 6,044
Quote:
Originally Posted by Treeman View Post
Yes I did seperate all of the grounds and tested them individually and then as a whole all ground points are good.
OK good , but I what I meant was to run a separte ground off compressor to known good ground, by pass the others
__________________
Ron
99 E320 THE Queen Mary
62 220b - Dolly - Finally my Finny!
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
07 Lexus RX 350 - Lexi
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
Reply With Quote
  #9  
Old 05-24-2011, 03:52 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
Quote:
Originally Posted by meltedpanda View Post
OK good , but I what I meant was to run a separte ground off compressor to known good ground, by pass the others
Yes I understand, I did that.

Is the only power source to the compressor coming from the switch on the regulator switck attached to the drier?
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #10  
Old 05-24-2011, 05:31 PM
meltedpanda's Avatar
Certified Benzaholic
 
Join Date: Mar 2003
Location: Central Ky
Posts: 6,044
thinking out loud here --- if the system is not charged to specs then the pressure switch may not be allowing the "full power" to reach the compressor. Low charge will prevent the unit from coming on at all , but thought that was an on off system. You changed out switch so assume good, but perhaps??? did you check for 12v on both sides of fuse??
Perhaps someone with a 77 AC system can cross check your wireing
__________________
Ron
99 E320 THE Queen Mary
62 220b - Dolly - Finally my Finny!
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
07 Lexus RX 350 - Lexi
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
Reply With Quote
  #11  
Old 05-24-2011, 09:54 PM
Yak Yak is offline
Registered User
 
Join Date: Aug 2009
Location: San Antonio, TX
Posts: 1,711
By "resistors" do you mean relays? You may just have a bad relay that isn't closing. A chattering resistor would be odd. A chattering relay means it's not staying closed.

Unplug them, clean the contacts, plug 'em back in.
Reply With Quote
  #12  
Old 05-24-2011, 10:20 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
Quote:
Originally Posted by Yak View Post
By "resistors" do you mean relays? You may just have a bad relay that isn't closing. A chattering resistor would be odd. A chattering relay means it's not staying closed.

Unplug them, clean the contacts, plug 'em back in.
DONE
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #13  
Old 05-24-2011, 11:31 PM
Yak Yak is offline
Registered User
 
Join Date: Aug 2009
Location: San Antonio, TX
Posts: 1,711
Quote:
Originally Posted by Treeman View Post
DONE
Does that mean success? Or just done?
Reply With Quote
  #14  
Old 05-24-2011, 11:41 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
240D York AC question Help!

Does the AC have to be fully charged for the pressure switch to kick-in, thus allowing the compressor to engage? I hope that make sense?
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
  #15  
Old 05-24-2011, 11:53 PM
Treeman's Avatar
Registered User
 
Join Date: May 2005
Location: Murchisons, Texas
Posts: 243
Quote:
Originally Posted by Yak View Post
Does that mean success? Or just done?
I cleaned them yesterday and replaced one using a relay I took off my parts car and it made the same noise.
I just dont get it.
I posted a question in the diesel forum asking if the system had to be fully charged to make the pressure switch active sllowing current to go to the compressor.
__________________
Collector of Fine Hose Clamps
'80 240D Kanarienvogel
77 240D 'AVA' is in heaven now
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 12:28 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page