wiring diagram for voltage regulator/alternator on 300D? - Mercedes-Benz Forum

Go Back   Mercedes-Benz Forum > Mercedes-Benz Sedan Forums > W123 E,CE,D,CD,TD,TE Class
New User? Register - Forgot Password

BenzWorld.org is the premier Mercedes-Benz Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 02-18-2010, 02:14 PM   #1 (permalink)
BenzWorld Member
 
Date registered: Dec 2007
Vehicle: drive: 1983 300D turbo ======== renovating: 1969 280 SE
Location: Lexington, KY
Posts: 79
wiring diagram for voltage regulator/alternator on 300D?

I'm blowing voltage regulators left and right at the moment(possibly due to my blower motor) and I'm trying to look into how I might build a better one that on this cheap replacement that I've been given. I'm seriously considering using like an old Mopar external regulator and just wiring it to the regulator that's in it now.

Anyone got a rough diagram of how the alternator/regulator wiring works?

I promise to share my ideas once I have a functioning system.

Thanks

Eric
__________________
1983 300D turbo
1969 280SE
--

Anarchy - It's not the law, it's just a good idea.
ehrichweiss is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 02-20-2010, 10:47 PM   #2 (permalink)
BenzWorld Elite
 
Date registered: Mar 2008
Vehicle: 1984 300D
Posts: 4,266
It would be helpful if you could give more info like the charging Voltage you are getting and at what speeds you are getting it at and what happens to the Voltage when you turn your Lights and accessories on.

In 2 years of reading on Forums I have not read of the Blower Motor causing blown Voltage Regulators.
But, you could remove the Blower Fuse and see if your problem goes away. That would prove the Blower is the cause of the problem.

I would be looking for a bad Ground (the V Regulator in this case controls the current to the Fields by grounding the regulator) or bad conections between the Battery and the Alternator.

There is a metal part of the Voltage Regulator (at one of the Retaining Screw holes) that contacts the Housing of the Alternator. If the Alternator Housing in that area is not making a good contact it will not ground well.
The Engine to Chassie Ground Strap could be unbolted and the contact area cleaned up so it makes good contact as well as where the Battery Ground Cable attaches to the body the Body.

Next, the Connector/Plug can also have poor conduction issues due to Oil, dirt, or oxidation.

On the Connector the 2 large slots with 2 fat Red wires should be getting Battery Voltage all of the time. One of the Wires goes to the Starter where the + Battery Cable attaches to the Starter.
I believe the other goes to the Terminal Block in front of the Battery (US models).
The smaller slot with the skinny Blue wire should get slighly less than Batter Voltage; but only when the Ignition Key is on. This is the circuit that goes to the Dash No Charging Warning Lignt.
The Bulb for the warning light is suppsed to be 3 watts or your Alternator will not charge.

Last edited by 300Dman; 02-20-2010 at 10:56 PM.
300Dman is offline   Reply With Quote
Old 02-23-2010, 02:15 PM   #3 (permalink)
BenzWorld Member
 
Date registered: Dec 2007
Vehicle: drive: 1983 300D turbo ======== renovating: 1969 280 SE
Location: Lexington, KY
Posts: 79
Quote:
Originally Posted by 300Dman View Post
In 2 years of reading on Forums I have not read of the Blower Motor causing blown Voltage Regulators.
But, you could remove the Blower Fuse and see if your problem goes away. That would prove the Blower is the cause of the problem.
Have you ever seen a blower motor blow a fuse? If they can do that, they can overload a regulator. Mine had been blowing 25 amp fuses every now and then so I'm pretty sure it's a good indication that the blower is a contributor. I've been working on cars(not just reading forums) since the mid-to-late 80's and have seen this(overloading the alternator/regulator) happen lots of times.
ehrichweiss is offline   Reply With Quote
Reply

  Mercedes-Benz Forum > Mercedes-Benz Sedan Forums > W123 E,CE,D,CD,TD,TE Class

Bookmarks



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Topic Author Forum Replies Last Post
Alternator Voltage regulator Merc600sec W140 S-Class 14 12-12-2011 12:30 PM
Alternator or Voltage Regulator? Gregs300CD W123 E,CE,D,CD,TD,TE Class 16 06-26-2011 08:41 PM
Alternator and/or voltage regulator? rharling W210 E50 AMG, E55 AMG 1 09-02-2007 12:13 PM
alternator and voltage regulator HELP! saporter W201 190 Class 5 03-28-2005 11:18 PM
Alternator Voltage Regulator ericdab G-Class 6 11-15-2004 10:49 PM


All times are GMT -7. The time now is 06:33 AM.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.1

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.