Mystery wire in engine compartment

Golf GTi Cabriolet 1986 Restoration. I have an unattached wire coming from the small loom that feeds the sensor on the RH side of the cylinder head. (RH when viewed from the front of the car looking backwards). The wire in question is a Brown and White. There is no connector on the end, so no clues. Al the sensors etc. on the engine are connected so there doesn't seem to be a home for this wire. Might be worth mentioning that I have a problem with the temperature gauge - it goes up to maximum with the ignition on but without the engine running and stone cold. Any suggestions gratefully received.

Only brown/white wires in the Bentley are for the Ox control unit,  or going into the oxs thermoswitch,

or from the ICM to the Hall Generator.

Maybe RubJohnny will have a better idea.

Have you got a picture of it?

Will try to get one tomorrow

I'd love to know the answer to this as I found a spare 2 wire female plug yesterday floating about near the servo and I dont remember removing it for the servo upgrade for anything

I think it might be the earthing wire that should go to the right hand rear rocker cover stud possibly. Do you have a wire going there?

It acts as an earth for the some of the gauges in the cluster. Hence why your temp guage is all over the place. Without the proper earth the resistance to the guage is in correct.

A picture of the area would be useful

Ian

WATERNAIR said

I'd love to know the answer to this as I found a spare 2 wire female plug yesterday floating about near the servo and I dont remember removing it for the servo upgrade for anything

1985  I'm pretty sure that one isn't used on the later cabs.
On the early small block cars the brake lights worked from a pressure sensor onto the Master cylinder. In later cars there's a switch on the steering column above the brake pedal. Hence the redundant electrical connection.

You'd have thought they'd have changed the wiring loom over the years wouldn't you?

Ian

borednow said

WATERNAIR said

I'd love to know the answer to this as I found a spare 2 wire female plug yesterday floating about near the servo and I dont remember removing it for the servo upgrade for anything

1985  I'm pretty sure that one isn't used on the later cabs.
On the early small block cars the brake lights worked from a pressure sensor onto the Master cylinder. In later cars there's a switch on the steering column above the brake pedal. Hence the redundant electrical connection.

You'd have thought they'd have changed the wiring loom over the years wouldn't you?

Ian

Makes sense, thanks for that

Oh and sorry for the thread hijack 

I think I've solved it! - Appears to be a feed for a bonnet light that was never there as it's the same colour combination as the boot light switch!  We'll see what it actually does when everything is back in place.  I have a ground to the cam cover stud already. I too have the 2 pole white connector hanging loose under the brake servo.

Bonnet light is not fitted by VW so someone else must of fitted it?

The white plug with the yellow wires near the servo is for the front fog lights which VW did not fit to many cars so that is why 99% of the time there is nothing attached to it.