Hello,

Trying to get all my lights working on the 48. I still have the 6 volt system. Do I need 6 volt bulbs for parking and tail/brake lights?

Thanks

 

Yes

 

And everything else that is wire to the 6 volt system. Tedd

 

For the life of me I cannot figure out why I have taillights both LH/RH.

Turn signals and brake light drivers side, however no turn signal or brake on passenger side.

Driving me nutzzzzzz

 

Chase it all wires with a multi-miter and see where the juice stops or if it is even starting. Check all the grounds if you haven't done so, also the bulb holders for corrosion even though it looks good. I've been where you are not too long ago, turned out to be the ground on the tail light bezels even though they were tight....Tedd

 

The taillight lamps have 2 filaments, one for the taillights and one for brake and directionals. Sounds like you have a bad bulb or a bad connection for the second filament.

 

If I have tail lights then can I assume I have full power to that bulb socket?

 

No because it's a separate circuit, the taillights come on via headlight switch, you can assume the ground side is ok though. The brake and directionals are routed through the directional switch. What you need to do is first check the bulb to ensure both filaments are intact, and second check for voltage at the socket with the brake pedal depressed and then with the directional selected with the key on.

 

I failed to mention that the Drivers Side front signal works......just not the rear......

 

Rule out a bad filament in a two filament bulb by putting a bulb that is known to be good (not just new) in the socket that doesn't work properly.

Good luck!!!

 

Most of the time is a poor ground issue.

Bob

 

I spent way too much time on it yesterday. Even thought of selling it.

My 6 volt bulbs will be here today. One last chance....

 

You'll never be able to sell it with lights that don't work! Walk away, take a break it's supposed to be a hobby/fun.

Good luck!!!

 

If it were a ground issue the taillights would not work either.

Have you checked the voltages or inspected the bulb?

 

I have new 6 volt bulbs arriving today.

 

This is what I'm working on......

 

Looks original and all there.

 

Thanks....just waiting for the mailman......6 v bulbs are in his truck,,,,

 

Must be an old mail truck then...

 

Is the Oldsmobile positive ground?

 

So here is the latest......

I had 2 factory wires on the passenger side rear. I thought one was for brake and one was for running and turn.

However I found a 3rd (Newer wire) that was back there and it was for my turn. I ended up connecting it to the factory wire and all lights now work.

I think it was added when the previous owner added the turn signal lever.

I put in new 6V bulbs and they all work. Not 100% sure what I did, however they work.

NOW - New issue.

Front parking lights. Passenger side does not work, however does work when turn signal is on.

It's a single wire as well......

I need to walk away for a while.

Positive Ground.

 

Put a little silicone grease in the bulb sockets and bulb bases in big and little bulbs.

This prevents rust and corrosion which prevents light issues. As they use to say - a little dab will do you.

A NEW battery post cleaner can be used to clean corroded contacts and inner shell for big bulbs.

Also use grease on headlight connection parts to help prevent dim lights.

You can carefully disassemble and clean the headlights switch then grease and reassemble.
​​​​​​
This works over a large number years and venders before and after 1948.

Ron

 

I think I see what's going on here.
Not all 1948 Oldsmobiles were equipped with turn signals from the factory. In fact, they did not become standard until 1952.
Turn signals were an option, and offered as a dealer installation package as early as 1941.
Various aftermarket turn signal switch kits were also offered.
Does the turn signal switch clamp on to the column? Or is it built in?

BTW the system is not positive ground. Positive ground was only found in some Fords and Mopar's.

 

Generally, or quite often, if a non activated light comes on when something else is turned on you have a bad ground back feeding to that light.... You still need to run the wires in question with a multi meter... Tedd

 

^^^^^^^^^^^^Agree

 

Yes - The turn signal switch mounts to the steering column. Looks NON-OEM.

It's odd to me that I have a parking lamp that works and a turn signal that does not from the same socket with only 1 wire going to it.

Maybe the headlight switch is taking a dump?

 

This may be close to how it's wired up for single filament front lamps. Disregard the ammeter as it may be getting power somewhere else.

 

X2, double and triple check!!

 

Try running a ground directly to the body of the turn signal switch. My friend just had a similar problem with an aftermarket turn signal switch, the added ground made it work.

Good luck!!!

 

Thanks...I'll try it tonight.