Connections on rear of '76 oil gauge

[Hil911]

Sorry to bother you all with this. I ran over the current flows and threads on here and cannot answer my question.

One gauge contains the oil temperature and pressure indicators. Each indicator has a +, a ground and a G. The G I believe is the line to the sender.

So: Pressure gauge G=Green/Red, Plus = Red/Black
Temperature gauge G=Green/Black, Plus = Red/Black

If that is correct then the question is the grounds. I have one connector with brown wires and one with green. So which one does the green wire go to? The current flow only seems to show the Red/Black and the sender wire.

I photographed it when I took it apart (to replace the glass) but some of the wires are hidden.

Thanks

Hil

[Hil911]

OK - well that didn't get a lot of response!

Maybe I rambled a bit. Am I right that there shouldn't be a plain green wire coming off the ground on the Oil pressure or the oil temperature gauges?

The only plain green on the 78SC circuit seems to be to the fuel gauge. Same on the 73 CIS.

I'm worried that if I connect it wrong there will be a big puff of smoke!

Thanks

Hil

[E Sully]

Brown is definitely the housing ground. I am not sure on the SC, but in my 1973 Porsche used a Green wire for the Sportmatic oil temperature. It is in the wiring harness but is left unconnected in non sporto cars.

[javadog]

I think the green goes on the ground on the temp gauge.

JR

[timmy2]

There is also a spare green wire in the '76 harness. If your fuel gauge has the green wire on it, then you have found the spare solid green wire that runs from the rear 14 pin connector T14 to T1e on the "luggage compartment floor" as shown in the CFD for the '76 on the legend page in the lower right center area showing all the unused wires in the harness: (There are at least 4 spare wires in the harness)
PM me your email address if you need the current flow diagrams for your '76
(Also a solid green to your wiper motor as indicated in the second picture.



Gauges:

[timmy2]

45 page thread here probably has a picture in it of the gauge connections.
If not, it is still a great read.
1976 911S – from garage find to on the road

[The cap'n]

Green is NEVER ground, and Brown always is. There are variations of the brown wire, but in the end they're always some kind of ground.

The Cap'n

[Hil911]

Thanks a ton Folks. My understanding is growing! I've owned cars for a long time but I guess have come to have less and less confidence in giving them to garages to fix. I now do almost everything myself but still need to learn a lot!

As a spin off from this, I am interested in seeing spare wires because fitting an alarm is in the car's near future. I like to be as devious as possible when I do that. Along the lines of "Ha ha - that's the alarm disabled ... what the heck ... the wheels have fallen off!"

Hil