W124 w/M104 electronic throttle actuator wiring is TOAST!

[JensenHealey]

I pulled the throttle body out of my 1993 300TE tonight and then disassembled it so I could examine the internal wiring.
The warnings about the condition of the pigtail harness were correct. The biodegradable wiring strikes again. It's weird though.
There are 11 different wires going from the external connector, traveling through a pigtail and connecting to a circuit board inside the unit and four of those wires seem to be just fine.
On those four wires the insulation is fine and the wires are flexible.
The other wires inside the harness are just 100% bare. No insulation at all.
Tomorrow I have to find a 9 volt battery so I can wires up some jumpers to test the internal clutch solenoid inside the unit.

 

[grober]

LOTS of video on YouTube how to repair these --this guy has posted a few.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

 

[JensenHealey]

I have watched quite a few of his videos already however he makes money repairing Mercedes ETA units so none of his videos actually cover exactly HOW to do the repair.
He charges $395 to repair the harness and if it also has a bad clutch solenoid that is another $150
I spoke with another place in the state of Georgia here in USA and their fee for doing the same repairs started at $800

I also came across a PDF document that does detail the actual repair process so since I am no stranger to soldering stuff I am going to give that a try.
I just hope my clutch solenoid is still functional.

The document I found was at http://www.w124performance.com/docs/mb/M104/M104_ETA_rewiring.pdf