Plan to replace the old switch panel on the steering wheel with the panel from the facelift. But in the old there is ground for goods from the control panel to the steering wheel. This earthing is not on the new one. Don't I need this earthing on the new one?

New Steering Wheel control panel

 

That grounding wire is for the horn. You will need it if you want a horn.

 

^^ Agreed...it is the wire for the horn.
Maybe it's missing off the new controls?
Without it the horn will not work.

Is it a new or used part you got?

 

This one is missing on my new control.

 

Can you transfer the ground wire from the old part to the new part? It's just one bolt holding it on.

 

The grounding wire is stuck to the old control wiring base. The bolt is for attaching this to the steering wheel itself. On the new control panels I want to put on, there is no grounding wiring. So I wonder if I can put on the new one without grounding?

 

First off, lets stop calling it the Grounding wire...it's not a Grounding wire. This is the wire to complete the Horn circuit...and yes, eventually it does go to Ground...but like every circuit in the car, they all eventually go to ground.
Toyota color codes Ground wires as white with a black stripe...in most, if not all, cases.

The Horn wire is supposed to go from the Horn pad (Airbag) to the Steering wheel.
You state that on the Old Control base the wire is stuck to it, and then bolted to the Steering wheel. If this is true, then there needs to be a wire that goes from the Old Steering Control to the Horn pad (Airbag).
As far as I know, the wire is supposed to go from the Steering Wheel to the Horn pad direct...there should not be another wire in between.

Also, in the pic for the New Steering Control, there appears to be a single terminal wire that looks like it can connect to the Horn pad (Airbag).
Is this the Horn wire?

 

Where is the other end of the wire that is attached to the screw?

 

Can this be swapped without removing the steering wheel? I know the airbag will need to be removed.

 

I'm thinking the controls are back bolted to the wheel maybe.
When you look at the pic above of the new part there's no bolt holes of fasteners that can be seem, so everything has to be behind.

 

@Pittsy Without seeing the two controls side by side, it's just a guessing game as to what needs to happen to make this all work.
I'm starting to think we might both be wrong and this isn't the Horn wire, but in fact is a Ground wire.
When he said the wire is "stuck" to the old controls, I'm assuming that means it soldered on...but once again I'm just guessing...and if I'm right then it's not the Horn wire, but really a Ground wire.
Maybe on the new controls they decided to integrate the Ground wire into the harness so the wire that was soldered and bolted on was eliminated.

@LexusFspor Does the new controls have a wire for the Horn?

 

 

Ok...seeing them side by side helps a lot!
So it is really a Ground wire, cause it's white and black...and both control sets have a Horn wire...so that's accounted for.
To go back to your last question, I would just install the new controls without the Ground wire.
Realistically the controls are both the same in terms of function, just the buttons look different, but do the same thing.
If they were able to eliminate the Ground wire, they must have accounted for it somewhere else in the connectors.
I would check the other connectors and make sure that all the same color wires are in the same place and make sure there are no wires missing from the old controls that are on the new controls.
If all wires are the same except the Ground, then go ahead with the install.

 

Just wondering, but does the Ground wire go into the black connector...i put two blue arrows that show where I think the wire is located in the connector:

 

Just wondering, but does the Ground wire go into the black connector...i put two blue arrows that show where I think the wire is located in the connector: Yes

No grounding on the new