Author Topic: 4 terminal electrical block under batter tray  (Read 279 times)

raueda1

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4 terminal electrical block under batter tray
« on: 18 May 2020, 05:39 PM »
As usual, I thought I took good enough pictures but of course I didn't.  [sidebar comment:  I've finally learned that no matter how many pictures you take, take more.  Like 3x more from varied angles, varied lighting, etc.  Otherwise you'll end up posting here earning everyone's scorn.]

I initially thought it's all easy - the 4 terminals are all different sizes, so just match then up the to the sizes of the ring connectors.  Now I'm not so sure and I don't want anything to fry. Can anybody confirm?  Thanks,
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

UTn_boy

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Re: 4 terminal electrical block under batter tray
« Reply #1 on: 19 May 2020, 02:19 AM »
I can't find any evidence of the 4 pole phenolic connector block on the U.S. models, but I seem to remember that my former Euro had the 4 terminal one, too.  The picture below depicts a U.S. model with what looks to be a 3 terminal block.  I figure if you can the three of the 4 connections figured out then the last set should be a no brainer.  Though, each terminal should be a different size to avoid this very confusion.  Also, the information in the picture below is in the repair manual....which you should have. 

Item number 107 is your starter motor, 98 is the alternator with internal regulation, and 108 is the battery.  To the top right corner of the alternator is the junction block in question. 

The top connector wires (three total) are WS/VI (white with violet tracer) and RS/BL (pink with blue tracer, all on the right side with a SW/WS (black with white tracer) on the left side.

The middle connector wires (three total) is WS/RT (white with red tracer) on the right side, and two RT (red) on the other side.

The bottom connector (two wires total) is WS/RT/VI (white/red violet) on the right side, and the left side has a RT/VI (red with violet tracer) wire.

 I hope this is somewhat helpful. 
1966 250se coupe`, black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3, papyrus white/dark red leather
1971 280sel Black/black leather
1973 300sel 4.5, silver blue metallic/blue leather
1976 280s astral silver/blue MB Tex

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #2 on: 19 May 2020, 06:49 AM »
Dave
I can get you pictures later today. Where is the four wire block located specifically?
Euro or us?

Jed
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #3 on: 19 May 2020, 07:03 AM »
Duh. I see, under battery tray. Euro. Got it.
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

raueda1

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Re: 4 terminal electrical block under batter tray
« Reply #4 on: 19 May 2020, 08:05 AM »
I can't find any evidence of the 4 pole phenolic connector block on the U.S. models, but I seem to remember that my former Euro had the 4 terminal one, too.  The picture below depicts a U.S. model with what looks to be a 3 terminal block.
>>>snip<<<

 I hope this is somewhat helpful.
Yes, thanks, more than somewhat helpful.  For the record, my US model parts car absolutely did have the same 4 pole block, exact same as the euro.  It was a '78.  I've got the schematic but hoping to avoid deciphering it.  My eyes are too old and tired.

By coincidence the shell goes to the crusher today.  Nothing left on it but still makes me fell kinda bad.  :-\
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

raueda1

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Re: 4 terminal electrical block under batter tray
« Reply #5 on: 19 May 2020, 08:06 AM »
Dave
I can get you pictures later today. Where is the four wire block located specifically?
Euro or us?

Jed
That'd be great.  Thanks much!
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

raueda1

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Re: 4 terminal electrical block under batter tray
« Reply #6 on: 19 May 2020, 09:45 AM »
This is now getting mysterious.  I scrutinized both euro and USA wiring diagrams and both just show that 3-terminal block associated with Starter/Alternator/Battery (SAB) circuit.  Yet on both of my cars (euro and USA) the block has 4 terminals.   Is it possible that the 4th terminal is for something else and therefore not shown on the diagrams as part of the SAB circuit?  All the connector rings are pretty clearly sized per the screw sizes so just going by that would be one way.  But, as I said, it makes me nervous.
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #7 on: 19 May 2020, 09:51 AM »
Dave I am looking at my 76 euro now. There are two 4 block terminals one mounted to the side of the battery tray And the other mounted to the chassis below it. I will send you pics of both as soon as I figure out how to do it on my phone. Not sure how much help they will be as the coloring on the wires is not at all clear.
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #8 on: 19 May 2020, 09:55 AM »
Does this help?
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #9 on: 19 May 2020, 09:56 AM »
OK let’s try this again. Not sure why those are zoomed in?
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #10 on: 19 May 2020, 10:02 AM »
Here’s a better angle
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

raueda1

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Re: 4 terminal electrical block under batter tray
« Reply #11 on: 19 May 2020, 12:12 PM »
OK let’s try this again. Not sure why those are zoomed in?
Yeah, I think so.  Thanks!  Yet there's still mystery.  Both of my cars just had one block, the vertical one.  You seem to also have a 4-terminal block that only has 2 connections.  And the vertical block 2 seems to have a couple single connections?  Seems odd.  Is the car pictured a euro 6.9? 
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

Jed

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Re: 4 terminal electrical block under batter tray
« Reply #12 on: 19 May 2020, 07:17 PM »
Yes. #484. 1976 euro.
I don't know what ANY of those wires are for but this car has a few weird factory options. External Temperature gauge, ammeter, dual horns,etc. I doubt any of those wires would be THERE but I really don't know.
« Last Edit: 19 May 2020, 07:24 PM by Jed »
1979 Mercedes 6.9 #5206 - restored
1979 Mercedes 6.9 #6424 - ongoing restoration
1976 Mercedes 6.9 #484 - restoration?

raueda1

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Re: 4 terminal electrical block under batter tray
« Reply #13 on: 19 May 2020, 08:31 PM »
Yes. #484. 1976 euro.
I don't know what ANY of those wires are for but this car has a few weird factory options. External Temperature gauge, ammeter, dual horns,etc. I doubt any of those wires would be THERE but I really don't know.
I'll eventually sort it out.  When I did I'll post. Cheers .
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0