New member, trying to get tail light to pass safety inspection

[TurboGirl]

I just bought a 1977 coupe, and as stupid as it sounds, since I bought it during daylight hours, I never checked to see if the lights work. The mechanic I had look it over didn't either. I've only driven in during the day since I got it (2 days), so when I went to get it safety inspected today, go figure the passenger side tail light doesn't work. The brake light on that side works, but no taillight. I had the bulbs looked at and they are fine, so that's not the problem. What else would cause just the passenger side tail light not work?

Sorry to barge in here like this, but I need to get the car to pass safety inspection ASAP. I will post pictures when I can drive it someplace nice to take them! Thanks!

[steely]

Welcome and congratulations.
You're either missing bulb power or a good return (to ground).
You could try removing the lens and bulb, and inspect the inside of the bulb socket. If the bulb itself was dirty/corroded, chances are the socket could be too.
Use a pen eraser inside the socket base a couple of times to clean it.

You could also be missing continuity in the ground lead, or the power lead.
If you have a meter, do a continuity to gnd for the brown wire / socket side (should be near 0 ohms), or do a careful +12V check with the meter to the inside base pin (tape around the meter lead except for very end) with lights on.
If you don't have +12 there, you'll have to follow the wire into the car to find where you do get power.
There is a schematic on the main page (left side) for 78s - not sure if it is the same.
hope this helps.

[kiwiokie]

The one of the contacts in the socket may have lost some of its spring and is no longer making good contact with the bulb. Try a gentle tug with a 90 degree pick tool hooked behind the contact (while ignition is off).

[Joe Bob]

You said you had "the bulbs looked at"? A third party I assume?

The brake and running light is a dual filament bulb. The running light runs the most and in most cases burns out first. It can in "most" cases been seen visually but in my experience I've had perfect looking bulbs be bad.

Did you switch bulbs side to side? A 77 is not a spring chicken anymore.....if it's not a fuse.....try spinning it, corrosion may be a culprit.

Get a test lamp or a meter and test the socket. If you have 12v in the socket (both terminals) try a new bulb.

[DRACO A5OG]

The sockets may be too loose. If you can wiggle the bulb when installed, you need a rubber O ring or two to give it a snug fit.

Using the pick tool will also give the contacts a re-fresh but the wiggle will cause the bulb not to make good contact and at times will cause the bulb to burn out pre-maturily. Use the pick too to push the o-ring snugly into the socket after installing the bulb.

I was installing OEM HONDA (made by STANLEY, USA) brake light dual filament 8watt bulbs ( recommended by Daniel Stern, definitely brighter) and found my rear turn signal was out, fuse and blub was good but the bulb was wiggling around in the socket. It was the OEM spec bulb with the oval contacts.

I placed an o-ring and VOILA, I have turn signal again

Jim