Pair of unknown wires in the rear of my 1969 912

[AirJose]

Hello all ,

I have two wiring diagrams for my 69. A 1969 and 1970 but can't figure these wires.

In both rear sides have 2 wires in each side, with the black plastic/vinyl factory insulation coming from each rear side of the wire harness. A light green and a brown wire.

The green has no voltage, no fog or rear lights will activate voltage for it. The brown is connected to ground as normal. They were rolled in the back in both sides and taped by the previous owner.

What are they for?
Any guesses?

Thanks in advance,

Jose

[ed mayo]

Probably for a sporto.

[timmy2]

Drivers side should be for rear fog lamp (euro) you need the correct type of fog lamp switch to activate it.
The passenger side should be for the oil tank level sender.
On the ‘69 make sure the single short wire coming from the male 6 pin connector is plugged in to the appropriate single loose wire in that same harness.

[AirJose]

Hello,

A little confused on the single short wire , I will check that.

Thanks!

[timmy2]

May not be there. Depends on which factory built the harness.

[SCadaddle]

I remember in my 69 912 there was a single wire on the drivers side (left) up near the voltage regulator. I want to say you touched it to ground* to make the engine start, supposedly a way for technicians to start the car while near the engine instead of using the key in the ignition. Been so long and the car is not near by right now. It wasn't something that was added by a previous owner, it was supposedly a "factory trick" and pointed out and demonstrated to me by the guy on the cover of the "911 Performance Handbook" back in the 90's.

*Can't remember if you touched this wire to ground or perhaps to the connector inside a single bakelite plastic connection under a bakelite thumbscrew cover in the very near vicinity of the single dangling wire. You might want to probe for voltage with the ignition "on" and have the car in neutral with the park brake on before proceeding!

[john walker's workshop]

Yellow wire, touched to a 12V source to work starter.

[SCadaddle]

Originally Posted by john walker's workshop

Yellow wire, touched to a 12V source to work starter.

Well there you go. Thanks John!

[mike sampsel]

Thanks for this info, my '78 has two wires on the rear drivers side, left after the shop installed my bumper and all my lights. I thought maybe they were for the rear fog light. Seems Timmy2 thinks so too. Wire colors were yellowish IIRC.

Learning is so much fun!