Numerical Temp Gauge change and question

[FenderGuy]

I replaced the stock temp guage with one with numbers, well on the back was a place where a light bulb went



So I put the light bulb and now it is red, i know i can live with it but what have others done when doing this conversion?

[Javers]

Isn't that the oil pressure warning light? If so the lamp should be wired to the oil pressure switch in the engine via a green/white (I think) wire. Lamp should only light when oil pressure drops really low or when ignition on but engine off.

Jon

[DaddyGlenn]

I was under the impression that this conversion made the oil pressure idiot light non-functional because the sensor did not have the separate connection.

[DaddyGlenn]

Never mind. That was dumb. Idiot light has a different sender all together.

[FenderGuy]

That is where the light bulb went which is really strange since it was blocked off from illuminating anything




This only turns on when the headlights turn on, it was taped off in the back before, I can live with it, but at the same time its annoying since its red. I had to put that light bulb somewhere.


Wondering why Porsche choice to do the the guage that way?

[Dennis Kalma]

The light you circled on the back side appears to be in a different position than the one you circled on the front side. My thought would be that is an illumination light (backside view) and is tied to the headlight circuit and illuminates the guage for nighttime viewing. It should have a white bulb and white reflector and show as white light of course.

The centre one still uses a white bulb but the reflector/cover must be red (obviously). Is there a chance that is the brake warning light? I am not near my car right now, but my recollection is that is the light that warns you when there is a fluid leak in one of the brake circuits....

Is there a chance you have the wrong bulb/socket/wires in the wrong hole? They are all mostly alike and I get them confused regularly.....

Dennis

[NY65912]

Fender, di you put the bulb in the holder that you have circled? It sounds as that the bulb is used for illuminating the gauge. The bulb should go into the holder on the temp gauge that you installed, not the red indicator.

Is this correct/ what you have done?

I did this same upgrade to my '80 SC and it was very straight forward.

If you need a pic of the gauge I will take one when I get home.

Good Luck

[FenderGuy]

Sorry guys for the confusion the above photo is my stock temp guage, the item ciricled is where the light bulb was at. It did not illuminate anything since it was blocked off from doing so by the holder.



When I replaced the stock temp guage with a nurmical guage, the numerical guage did not have the bulb holder as the stock unit did. So I placed the bulb in the empty holder. Hence why its red now.


Dennis I believe you are right about that being for the brake warning light, but my guage did not have the brake warning light installed, it was just taped off and empty, so I placed the bulb there.


Can I take the bulb out so it doesnt illuminate red everytime I turn the lights on? This wont cause it to short?

[PSJoyce]

Not sure this helps a lot, but this is what I had when I did the same to my 1985.

The first photo is of the back of the numeric gauge I purchased from Pelican – it does have a bulb holder.

The second is of the back of the gauge, with the original non-numeric panel in place. It does show the oil light in the upper center hole. This was before any modification.

All the gauge lights work properly in my car

Hope that helps some

Paul

[Dennis Kalma]

You can take the bulb out, but make sure that those contacts are insulated. They will flop around and eventually make contact with ground....and then considering there are a number of circuits that are not fused...you will let some of the magic smoke out and things will go dark.

I had a short on my heater lever illumination light, the escaping magic smoke melted a number of ground wires and other wires to boot before I clued in and turned the lights off.

If you are sure you would never use the bulb again (I would trace it to see what it really is supposed to be....easily done as all wires are pretty well colour coded) then I would clip the holder off, put a piece of heat shrunk tubing over the end, then bend it over and wrap electricians tape over the end.....

Have I told you I am anal and paranoid about all the people ane other electrical spirits who are chasing me?

Dennis

Dennis

[DaddyGlenn]

Fender, Did you replace the whole guage or upgrade your old one?

[FenderGuy]

Paul

Yeah I see the Pelican unit has a place for the bulb holder, I bought a 73 tempe guage so it didnt have it...


Dennis thanks for the advice, I may just keep lit until I replace my air/heater unit and replace the bulb there since its got several empty bulb holders

Glenn I bought a 1973 temp guage untit off Ebay and just replaced the stock temp part with the number unit ..I had to get a new sender though, but it took about 10 minutes to change out and now I have numbers guage instead of the stock unit

[DaddyGlenn]

I've just added this to my "to do" list.