Resistors
To remove the faulty light error resistors must be placed between the mass cable and the LED cable. This will draw enough electricity to fool the canbus system so the chrismast tree on the dash will disappear.
To make it easy for myself I did not solder the resistors to the new cables.
Instead I put plugs onto the cables so I could plug and unplug the resistor.
I used these on the new cables:
They wrap around the cable and pierce it. On the other and you can insert a flat plug.

I welded a bit of cable to the resistors with the plugs. I forgot to make pictures but this is the result.

And the resisor fitted:

The error on the dash disappeard
Update:
To make it easy for myself I did not solder the resistors to the new cables.
Instead I put plugs onto the cables so I could plug and unplug the resistor.
I used these on the new cables:
They wrap around the cable and pierce it. On the other and you can insert a flat plug.

I welded a bit of cable to the resistors with the plugs. I forgot to make pictures but this is the result.

And the resisor fitted:

The error on the dash disappeard

Update: