Transmission sensor?
 

https://farm6.staticflickr.com/5222/...43718ff3_o.jpgHi - I recently purchased a '73 914 2.0. I am in the process of disassembling the car. Preparing for the engine drop, I saw a sensor sticking out of the gearbox, just behind the left rear axle.

What is it?

https://flic.kr/p/nn3rb4

Back up light switch. When you put the transmission into reverse, a pin pokes out of the transmission into the switch, and shorts the two wires together. That is used to power the back up lights.

Those wires are added on--the sensor itself may have been messed with on your car. The stock ones basically have bullet connectors that push into the holes in the switch.

--DD

Thanks for quick answer Dave! I'll add it to my to-do list and check it out. Lots of 'custom' wires on this car and the parts list keeps on growing and growing...

I am hijacking this thread... sorry in advance.

My reverse sensor is functional... I bench tested it but in real world settings it fails to turn on the reverse lights... it seems that the plunger is either not long enough or the mechanism that pushes on it isn't pushing far enough.

Any thoughts?

The plungers can wear. I have heard of people fabricating new ones--even of people using an old drill bit as a new plunger, as long as the length was right!

--DD

I fabricated a plunger from a rotary-tool bit, I even cut in the groove for the c-clip. it fit PERFECTLY. Now I have reverse lights for the first time in over 17 years!

Thanks for the idea!