Mercedes W109-4.5 Wiring Harness Challenge

[lpeterssen]

Dear friends

I am in the middle of a challenging harness set project for a customer in Saudi Arabia.

This is a harness from a very rare car W109-4.5 300SEL which total production number is in the range of the 2,500 units.

Certainly it is a very demanding project/customer with a harness considered trash for anybody. It was chopped at the firewall  entry point.

The harness rest shown on picture had a repair attempt before me.

The condition of it obligated me to built all circuits from scratch with no splices anywhere.   That process has been developed in detail matching in 90% de original cable color scheme.

Wish me luck

Best regards
Leonardo Peterssen
Www.wiredoktor.com


https://www.icloud.com/sharedalbum/#B0Q5Q2ydoG6KCEG

[RAY]

Wow, unbelievable what you do, I would not know where to start.

I don't think you need to much luck, from your past posts you appear to know exactly what your doing but what I think you do need is a lot of time and patience.

But good luck anyway.

[lpeterssen]

Ray

Thanks a lot.  I think the key conditions are to be patient and organized.

Best regards
L.Peterssen
Www.wiredoktor.com

[Baybear]

I have a 1972 300sel 4.5. If I can help in any way with pictures etc. Let me know. Only 2553  of these made from 1971-1972 at a cost of about $14,100 US.
Will

[lpeterssen]

Dear Will

Many thanks for your kind offer.  I am using as a guide another wiring harness set I have from a similar car:

• A harness set from w108-4.5
• A harness set from a w109-300 with  M189 engine

But nevertheless I got one cable branch which is chopped inside the cabin that I have not identified according to wiring diagrams what for it is.

There are two cables, one light green going together with a blue wire.  Those are close to the connector for the AC EVAPORATOR UNIT below the dashboard.  I have no idea what for are they?

It is not related to the FASTEN SEAT belts warning system.

It may be related to the AC system, maybe it feeds a bulb on the ac control panel ,to let the user know when the compressor clutch is engaged…..

If you have any ideas… will be received with joy.

Best regards
Leonardo Peterssen
Www.wiredoktor.com

[Baybear]

The car is currently about an hour and a half away in our second home in Deltaville, VA. I should be able to go down there on Thursday and see what I can do. Perhaps take some pictures from underneath the dash to help you. I assume the wiring harness on a 1970 6.3 is different. I have one of those in my garage here in Midlothian, VA.
Will

[lpeterssen]

Dear Will

Yes the harness from a w109-6.3 is totally different.  I have one full harness set of those here and I also own a w109-6.3 1969.

I will send you a PM to stay in touch.

No problem if you can go over the 109-4.5 on Thursday.  Still have lot of work on this harness and that can wait until many other things are sorted out.

Best regards
Leonardo Peterssen
Www.wiredoktor.com

[lpeterssen]

Dear friends

I am getting there. What appeared to be impossible is now close to its final completion.

The w109-4.5 chopped harness has become the pristine beauty shown on pictures attached.

The customer is more than happy with the outcome.

1. All relays changed to cubed style pin arrangement
2. Fully functional emission control
System
3. Intermittent wipers rare option added with original Mercedes Impulsegeber relay
4. Matching 3 speed steering wheel switch added

Here shared album link with high res photos and comments

https://www.icloud.com/sharedalbum/#B0Q5Q2ydoG6KCEG

Best regards
Eng.Leonardo Peterssen