Wire Identification - Main Fuse Panel

[Walt Marsh]

Hello Pagoda Group Members,

I am restoring a late U.S. Model 1971 280SL to factory specs.
Vehicle equipped with AC, Automatic Transmission, Power Steering, etc.

I connected wiring harness to main fuse panel with assistance form the U.S. 280SL Color Wiring Diagram, Headlight Switch Diagrams, etc.  located on this site.
Been real lucky so far except for last wire.
I know it is part of original loom and based on its proximity it's reasonable to assume it connects to main fuse panel.
Clearly, my problem is that I am unable to locate same wire color coding anywhere else on vehicle.
I've double checked and disconnected every Connecter in hopes of turning up a red/white/ with blue streak wire but am unable to find one.

Note: Wire is Red/White with Blue streaks. (See image below)

Does anyone know where it goes to, connects to, or what it's for?
Any help much appreciated.


Walter Marsh

[Jonny B]

Walter,

Did you take a look at the color wiring diagrams posted on the Technical Forum (wiki)? There is also a black and white copy of a US 280 SL wiring diagram that identifies the various wires going to the center cluster. The center cluster on the diagram is labeled 10. As best as I can see from the smaller screen on my PC, the wire (going to 10 c) is blue/green - need a second set of eyes on the diagram. Could it be 10g, the alternator light??

[Walt Marsh]

Hello Jonny B,

Yes, I have been using Pagoda Group's resources and the wiring diagrams and information are excellent.  
However, the color wiring diagram is not a good representation of my vehicles wiring loom.
Several other 280SL's in the shop also do not reflect color wire diagram depiction.
It seems, every time the U.S. changed emissions Germany changed it's wiring and color combinations.
Unfortunately, in this instance color wiring diagrams not very helpful.

Center instrument cluster works fine except the "red" reserve light refuses to warn of no fuel in Gas tank.

Walter

[Jonny B]

Bummer information about the potential for different kinds of wires!

[Tomnistuff]

I know that this is an attempt to grasp as straws, but here goes.  You mentioned AC.  These cars were not made with factory AC.  It was a dealer installed option, so I would suggest that this wire is perhaps associated with the AC system.  If so, there are only a couple of possibilities to check out.  Since it's not brown or black, it's not likely a ground wire.  You might try attaching a trickle charger to it an see if you can find power at some other terminal.  The wiring diagrams don't show AC wiring because MB did not design AC systems for these cars.

If I'm wrong, please forgive me. 

Tom Kizer

[Walt Marsh]

Hello Tom,
 
The mystery wire is part of the original wiring loom.
As you stated A/C units were U.S. Dealerships install.
Therefore, A/C wiring harness is not a part of the original loom.

I have an original Mercedes Benz Service Manual (See Image A Attached) and have referenced the section on "Connectors & Leads of Main Wiring Circuit"  (See Image B, C, D Attached) in hopes to resolving this quandary.
However, the services manual itself make special note that the "Connectors & Leads of Main Wiring Circuit" depicted are for all vehicles models contained in the manual except 280SL/8. -"Vedamt noch mal!"

However, if I disregard the service manuals notation - I find there are 3 possibilities where a red/white and blue streak wire could possibly go based on the color combinations for these other models.

Walter

[66andBlue]

.....
It seems, every time the U.S. changed emissions Germany changed it's wiring and color combinations.
Unfortunately, in this instance color wiring diagrams not very helpful.  ..

Hi Walter,
don't jump to conclusions too fast !
Your red-blue-white wire goes from fuse #1 to the steering column switch #29 (on Achim's colored wiring diagram in the Technical Manual) terminal "b" -  headlight flash switch.
No, Germany did not switch wiring and color combinations.
What about switching to new glasses - or perhaps use a magnifying lens?  

[114015]

Your red-blue-white wire goes from fuse #1 to the steering column switch #29 (on Achim's colored wiring diagram in the Technical Manual) terminal "b" -  headlight flash switch.

Hello Walter,

Alfred's synopsis is absolutely correct here.

US-delivered cars (from VIN ?? onwards) did not have a functioning headlight flasher anymore.
The only difference was that this particular wire in your hands (the 1.5 square millimeter red wire with white and blue lines) was not connected on these cars. But the wire has always been around on all factory original cars.

Thus, you only need to reconnect ... no! - connect it for the first time in its life with fuse no. 1 - and there you go.
Then you will have headlight flashers as well.

Good luck & congratulations on your fine car

Achim
(the wiring-diagram guy)

[Walt Marsh]

Thanks to everyone's suggestions.
I installed the White/Red/Blue streaked wire on one position #1 main fuse panel.
Unfortunately, the high beam flasher on the column switch doesn't function but I'm assuming it's probably because it's not a european column switch.

Thanks Again,

Walter

[66andBlue]

The high beam flasher does not work on US version cars because the handshake connection was left open. See: http://www.sl113.org/wiki/Electrical/SteeringColumnSwitch
You need to add the wire terminals in position #5 (your white/red/blue wire) and #8 in the female connector.
Generally speaking there are no different "European" or "American" parts on W113 cars with the exception of the headlamps and unit lettering on gauges and instruments, that is, mph/kmh or C and F, etc.

[Walt Marsh]

Thanks Again Alfred!
I rewired the handshake with a couple of simple re-soldering of connections and routed them to their missing Pin positions 5 & 8.
Works like a charm!

Walter