'74 Carrera parking light indicator question

[steve meltzer]

I just took the speedo out of my '74 car and noticed that there's no bulb, bulb holder nor even any wires for the parking light indicator in the gauge. In fact, when you look at the back of the speedo, the orifice for said bulb/holder is all corroded, meaning there's been nothing in the hole for years. Any thoughts on this? Notta critical issue, but annoys my obsessive personality. thanx steve

[SpyderMike]

Do you see a loose bulb holder behind the dash in that location?

[steve meltzer]

Nada. no bulb holder, no errant wires. etc. thanx steve

[SpyderMike]

Looks like it should be a white/green wire from location 57 of the light switch...do you have such a wire on the light switch?

[steve meltzer]

oooh. ooooh. (said like Gunther Toody on "Car 54") i'll have to look in the AM. Good thinkin'. While cogitating on this at work, i thought i'd best check the wiring diagram, which I still haven't done. s

[SpyderMike]

All I could find was a schematic for a 1972....pretty consistent they (Porsche) are though on that I think. Easy enough to add it if you want it.

[steve meltzer]

I've got the '74 schematic, but well into a nice 'rita, think i'll check it in the AM. thanx steve

[steve meltzer]

Spyder Mike....thanx again....good thinkin'....of course the light switch on the dash has a white wire/green stripes. So, I went back to the hole where the speedo lived before going to the shop, and Bingo....Wayne N. DeBack, was the white wire/green stripes devoid of anything....no bulb holder, no spade connector, just snipped off bare wire. I'll get a bulb holder and we should be all set. thanx again. steve

[SpyderMike]

Congrats on solving it!

[steve meltzer]

yep! i had great help! cool. s

[69porsche]

I can only assume you have never driven the car at night?----- must have just bought it

[steve meltzer]

yep, as my signature says "new to me"...I have driven it at night, but prefer not to. But in my own defense, the circumstances under which one would use their parking lights alone are rare, so I never looked at the speedo for the indicator. But, my compulsive nature wants as much of the stuff to work properly if possible and financially reasonable. thanx. s

[steve meltzer]

OK, i got a bulb holder/socket from a nice guy on eBay (dporschepartsman). All wired up and works great except that the socket won't fit in the orifice for the parking light indicator (too big in diameter) but fits great in the other available orifices on the back of the speedo. Is the bulb holder for the parking lights indicator different than the ones for the other functions on the speedo face? thanx s

[ossiblue]

Originally Posted by steve meltzer

OK, i got a bulb holder/socket from a nice guy on eBay (dporschepartsman). All wired up and works great except that the socket won't fit in the orifice for the parking light indicator (too big in diameter) but fits great in the other available orifices on the back of the speedo. Is the bulb holder for the parking lights indicator different than the ones for the other functions on the speedo face? thanx s

Only a guess here, but are you certain that the hole for the parking light is completely clear of the old bulb holder? Meaning, are there any remnants of the old holder still withing the opening--I'm thinking the outer shell of the old holder may still be inserted into the hole.

[steve meltzer]

what an excellent thought! i'll have to check...it didn't look like it, but this is so weird that it would be worth a re-look. thanx for your great idea. s

[steve meltzer]

OK, if you look down the bore of the two orifices that will accept this bulb/holder, they are clearly a c-hair wider and have two grooves within the hole...not present on the opening for the parking light bulb. That (for the parking light indicator bulb) orifice appears and feels to have a sleeve, or insert that goes down about halfway...no grooves, more narrow, than the other two. is the correct? can i very slowly, spin a drill bit to widen that opening? arggghhh. thanx steve

[steve meltzer]

LJ, i believe there is some casing from the old bulb, but WOW! it's in there tight. Tried with a pick but no luck so far. thanx steve

[ossiblue]

Originally Posted by steve meltzer

OK, if you look down the bore of the two orifices that will accept this bulb/holder, they are clearly a c-hair wider and have two grooves within the hole...not present on the opening for the parking light bulb. That (for the parking light indicator bulb) orifice appears and feels to have a sleeve, or insert that goes down about halfway...no grooves, more narrow, than the other two. is the correct? can i very slowly, spin a drill bit to widen that opening? arggghhh. thanx steve

This is all from memory so take this with that caveat.
Here is a picture of the back side of what I believe is a 74 speedo.



Does yours look the same? Here's a link to the site where I got the picture. https://rennlist.com/forums/parts-marketplace/1037101-fs-porsche-speedometer-odometer-gauge-for-1974-1975-911-a.html

If yours looks like this, it appears that all the holes are the same size and the bulb carriers appear to be the same as well. You might let us know if the parking light hole has a "lip" around it, as that would indicate the guts of the carrier are gone but the brass shell is still inserted. You can see the lips of the bulb carriers in the picture.

[timmy2]

Should be a ba7 metal cased single wire bulb holder.
Not the plastic 2 wire type.
You can get one for a VW with a .250 tab.

[steve meltzer]

i was getting confused there, but that is the back of tach, as you said, but my problem is the back of the SPEEDO! is the bulbholder/socket for the parking light indicator different that the one for the other two functions??