67 Delta 88 hardtop

I'm trying to work through my car to get it driveable and this is #1. My brake lights work great new bulbs and switch but when I turn on my lights only the headlights come on. no tails. where should I start or what should I do?

jaunty75

The first thing is to check the taillight fuse. If that's ok, you'll have to trace the wiring and look for any breaks in it. The fact that neither taillight works suggests a problem up front. The headlight switch might also be a problem.

I have a '67 Delta 88 convertible, and 1967 Oldsmobile Chassis and Body service manuals are indispensable for problems like this. If you don't have these, they should be your next priority.

A wiring diagram will show you the exact taillight circuit, including what the colors of the wires are, and you can check the correct wires at the headlight switch.

When you say "new bulbs and switch," which switch are you referring to? The headlight switch or the brake light switch? A new headlight switch is only about $10.00, so if yours is at all questionable, you should replace it if you haven't already.

67 Delta 88 hardtop

Thanks. I was talking about a new brake light switch. I'll pick up a new headlight switch on the way home from work. I haven't gotten in there to test the wires yet so I was just wondering if there was anything obvious I should do first. The brake lights light up just not the taillights. is there a seperate fuse?

Lady72nRob71

On many cars, there is a separate fuse. It is marked TAIL on the 72 fusebox. Side marker lights and parking lights and sometimes dash lights feed from it too.
Either replace it with a known good fuse or measure on both sides of it. Just looking at it is not enough. Sometimes the ends inside the glass break.

67 Delta 88 hardtop

this problem might just get everything fixed at once. I don't have dash lights or reverse lights or side marker lights either. that would be GREAT!

jaunty75

Yes. The brake light fuse (labeled "stop lights") is 20 amp, while the taillight fuse is 15 amp. You need to get under the dash and check the taillight fuse.

The dash lights have a separate, 3 amp fuse also in the fuse block. You should check that fuse, too, but if both the dash lights AND the taillights don't work, that's beginning to sound more like a bad headlight switch. But checking the fuses doesn't cost anything, and I would do that before purchasing and going through the bother of installing a new headlight switch.

jaunty75

Side marker lights? What side marker lights? I don't have any side marker lights on my '67!

jaunty75

The back-up lamps are on still yet another circuit. There is a 9-amp fuse in the fuse block labeled "INST B/U". Check that one, too.

67 Delta 88 hardtop

yeah. I haven't spent much time with my car as i'm in school and the car is at home. I figured I'd say that just in case. I guess even if I don't have them they still don't work

jaunty75

They became required by law starting in 1968, I believe. But I think some 1967 cars had them. Mine doesn't, though. But I think our cars could have been had with cornering lights, so having lights on the side isn't out of the realm of possibility.

Rickman48

I just had a simular situation with a '65 Nova!
Curved plug from the steering column was loose - pulled it apart and pushed it in hard corrected it!!

67 Delta 88 hardtop

update. 12V on both sides of fuse. new switch and still nothing. I'll have to start checking wires or something. where inside the car are they run? they come into the trunk in the middle of the back seat.

Each socket has two wires going into it. one is for brakes. Is the other tails? It checked out at 0 ohms to ground so if so thats the problem.

jaunty75

If you have a short somewhere in the system, you would expect to find blown fuses. If the fuses are not blown, then it's more likely that you have an open in the wiring somewhere.

There's no point in anyone here trying to describe where the wires go, and there isn't likely to be a single, magic answer that will lead to an immediate solution of the problem. Just get to it. Start at the taillights and work backwards. You may have to remove seats or trim or whatever here and there to follow the wiring, but that's what it's going to take.

Lady72nRob71

If you have metal sockets, the tail wire should be dark brown and the brake/turn section may be green or blue or something... Plastic sockets may have a third ground wire which may be black.

Make sure the bulbs are correct (3 filament type) and installed right - they can be forced in wrong... Ohm the bulbs, too. I have seen instances with multiple bulbs fried, esp. if the voltage reg failed high voltage before then.

If the obvious passes. then follow the wiring harness from the bulbs forward, looking for damage or bad connectors.

Let us know how it goes.

67 Delta 88 hardtop

I wasn't looking for a magical answer nor would I expect one(but wouldn't it be nice). that aside...... there is a yellow and purple? wire going into the socket. yellow is brakes. is the other wire for the taillights or is it a ground?

Rickman48

I've seen the ground wire on various GM cars come in anywhere from the left inner wheelhouse to the left side trunk floor/taillight panel - usually out of the taillight loom.
Trace from behind the rear seat - it'll be there!!
Usually black!

67 Delta 88 hardtop

thanks LadynRob. thats what I was wondering. I didn't post quick enough to see your post first. I'll check it out tonight. what I would give for a heated garage!!!!!!! It's in the negatives here today.

67 Delta 88 hardtop

I have plastic sockets that ground to the taillight housing with metal clips when inserted.

gmilner

Hey 67 nice car. I have a question that I hope you can answer? Can a Delta 88 hood fit a 68 oldsmobile 98 convertible?

67 Delta 88 hardtop

67 won't fit on a 68. other than that i'm not sure.

jaunty75

For the same year, I think the answer is yes.


Here's a '68 98





Here's a '68 Delta 88




To my eye, the hoods look very much the same.

aliensatemybuick

I think a bad headlight switch is the likely cause of the problem you describe...start by checking the leads to the switch (maybe some are loose or off under the dash). If that's not it, the switch may be broken. I've even seen where the plastic switch housing cracks and causes such a failure.

Lady72nRob71

If these are 2 filament bulbs, then there will be at least one wire for tail and one for turn/stop. Sounds like yours ground through a clip. If there are 3 wires, then one is a ground.

Assuming you have 2-wire sockets:
Look at the two wires from the left and the two wires from the right.
The color that is common to both L and R would be for tail (I think this is brown).
Yes, the 67 may have different colors for stop/turn like yellow or purple. My example was for 1972 - sorry for the confusion.

I think it is a bit nippy in your part of the country! We will see 60* this afternoon...

gmilner

Thanks Jaunty 75 for the eye shot. It looks the same to me also. Would the bumpers as-well-as the park light covers fit also? This to also looks the same.

jaunty75

Yes, they do look the same. Olds tended to make the 88's and 98's identical from the firewall forward starting about that time. I know that this is not true for '67, but for '68 through '70 they look the same. From '71 forward they WERE the same.

67 Delta 88 hardtop

Wow, it's been a while! I figured out the taillights and along the way I realized the domino effect that these cars have. New carpet, new seat foam and covers, new insulation. And i'm sure thats just the beginning. I was at school away from the car until about 2 weeks ago and man its been fun getting to drive an american boat instead of my other car (infiniti g35). Even though it looks like crap on the outside people still respect the old cars thats for sure. Now I just have to get a muffler on it... I feel bad driving around after 10PM haha

A2Mechanic

what was your fix for the taillights!??

m371961

This post is over 6 years old. Why don't you introduce yourself and your ride and post your light troubles in a new post?

jaunty75

And the last time the OP visited the site was in December 2011, according to his user profile, so he's long gone.