Schematics for right ETA

Since I have now started the car and it runs fine, here is the schematics for the passenger side ETA:

ETA pin Connector pin Original colour
b 3 White/Brown
Motor +, upper 4 White/Black
i 5 White/Green
g 7 White/Yellow
e 9 Grey
Motor -, lower 11 White/Blue
k 12 White/Purple
c 14 Brown/Red

Fire it up!

You should be able to fire it up, even if you have done like me and removed the LMM wiring, however, it might run a little rough. What you will need is to put the the filters, LMM, rubber bends and so on back. Without the correct resistance for the inlets it will more or less instantly go into Limp home mode.

Putting the ETAs back in the car

There should be clamps on the rubber tubes that are underneath the ETAs, they were missing, so replaced them with stainless ones, the real ones are just spring loaded.

Also take the opportunity to grease up the linkages for the throttle:

I also usually put some aluminium paste on the screws:

Connect everything as it was, I put waterfree grease on all electric connectors, the one I use is for putting on battery connectors, but vaseline will do you just as fine, important it is has no water in it:


Finishing right ETA

Time to get going again, get your soldering gear out and assemble the ETA again.

Wires for the small motor, black is + here:

All the other wires, as usual, check, double check and check again:

I lock the cable with a glued zip tie on the inside and then glue it to the plastic sealing ring aswell, remember the locking ring:

To make it completely waterproof and lock the cable even more I seal it off with heatglue, I heat the outside of the aluminium housing to so the glue gets like water and penetrates everywhere:

Alright, that was the easier one….:

New ETA wires

Some new wires soldered to the pins according to the mapping done earlier. Mercedes has not followed any such as Red = +, Black = -, probably because most of the leads are data, but not even for the Electric motor, Black/White is +. So I just try to match up a good colour and document it, besides, the wires I use only come in about 10 colours. I use a wire with Radox 125 or 155 sheathing, they withstand high temperatures and chemicals, the wire tube I use is glass silk silicone and withstands high temperatures and chemicals also. But I guess any good products should be fine, this has worked well for me.

8 wires in total, 3 different wire dimensions, 2 different sizes of pins on the left side:

Make sure you put them back in the right position, a Little bit tricky to get the black surrounding back, when done, double check your wires are in the right position and then check again…:

Lets make a cable from this:

Sheathing with shrink tube on:

Had to drill the hole a little bigger, 10 mm to fit the cable nicely after the shrink tube made it fatter, Mercedes put some sealing gooh there:

Glue all joints to make it waterproof:

Done! Also with some more shrink tubing going over the end of the connector, just needs to be joined with the ETA now, but that is the easy part:


Cut open the ETA connector

I have used a knife and hammer, a Dremel-tool and this time a small hacksaw to open the connectors. Hacksaw is by far the easiest and most secure. Cut along the mould line and then pry the halves apart:

Pry the two halves apart, make sure to note which way they were, since there is both alignment hole in the middle of the connector as on the outside of it. If you get this wrong the connector will not fit the socket in the car:

Seen better:

There are two small locks on the black plastic surrounding:

Time to get your soldering iron out again:


Right ETA cable

Time to remove the cable from the ETA, first remove this ring and then yank out the cable, it has a plastic locking ring with a O-ring:

Remove the plastic locking ring, you will need it later, this is done by brute force, cut the cable on the short side as close as you can and just take it from there:

Some compressed air and some alcohol later you have this:

Remember, the more high finish the air intake is the easier the car breathes… 🙂

Mapping of right ETA

Before starting to touch things too much you will need to do some mapping of the wiring. I have found that the wire colours are unfortunately different between the cars I have been dealing with. So, get some really good photos of everything you do, has saved me many times and make a table of some sort for the wiring. This is what I use in Excel and of course it is in Swedish, but you get the point. I measured the wires to get the copper area, and then bought new ones accordning to the table. Unfortunately I haven’t located the exact wires and I use high grade wires so I tend to go for what is closest.

Spjällhus pin Kontaktpin Originalfärg Ny färg Ny kabelarea mm2
b 3 Vit/Brun Brun 0,5
Motor +, övre 4 Vit/Svart Svart 1
i 5 Vit/Grön Blå 0,75
g 7 Vit/Gul Gul 0,5
e 9 Grå Grå 0,5
Motor -, undre 11 Vit/Blå Blå 1
k 12 Vit/Lila Vit 0,75
c 14 Brun/Röd Röd 0,5

So, get your multimeter out and start by cutting one wire at a time and see where it ends in the connector which is clearly marked with numbers, same goes for the circuitboard which has letters:

The wires for the motor are however not marked on the soldering points, I basically call them top/bottom and have once researched which one is + and -. But anyway I simply write with a permanent marker what pin they go to:

The pastel coloured wires are “internal” and should remain, time for some cleaning and removing leftovers from the wires:

I resolder all resistors and wires and wipe the old flux residue away: