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I just purchased a 1965 Oldsmobile 98 four door sedan and I'm trying to figure out how the lighting is supposed to work. If I open a front door, or a back door, does all of the courtesy lights illuminate, or just the front area or back area.
Currently I found that all of the bulbs in the rear area have been removed. I went to install some bulbs but discovered that they stay on all the time, so there must be a ground somewhere. The front lights seem to work fine. They light up when I open a front door and nothing happens when I open a rear door. Ideas?
I just purchased a 1965 Oldsmobile 98 four door sedan and I'm trying to figure out how the lighting is supposed to work. If I open a front door, or a back door, does all of the courtesy lights illuminate, or just the front area or back area.
Currently I found that all of the bulbs in the rear area have been removed. I went to install some bulbs but discovered that they stay on all the time, so there must be a ground somewhere. The front lights seem to work fine. They light up when I open a front door and nothing happens when I open a rear door. Ideas?
If they are on all the time then you must have a short circuit somewhere. There should be a switch where the door meets the body. When you open one door all the courtesy lights will turn on, when you close it the switch is pressed in and the lights turn off.
Ok, that means all lights on the same circuit. The previous owner must have separated the front from the back because the circuits are now independent. I'd have to pull out all the carpet and trace wires. I guess I'll save that for a future project. On the bright side, the front courtesy lights all work, and the map light. The vanity light under the mirror (back of front seat) also works. I'll focus on more pressing things for now. Thanks for the info. The folks on here are very helpful. This car has kept me busy for the past few weeks. It's almost ready to drive. I just have to go to the DMV and get the title switched over to my name. Fun stuff.
These lights are powered from the battery through a dedicated fuse in the fuse block labeled “COURTESY LGT” or similar. When there’s a short, it’ll just pop fuses all the time and very quickly.
Your 65 should have the earlier large diameter door switches where as my ‘66’s have the later smaller diameter plunger switches. The circuits are open when all doors are closed. Then when you open a door the loading spring closes the switch and the bulbs light up. The courtesy lights can also be turned on with the light switch by turning the **** all the way clockwise.
What that means is that each bulb has 2 positive side leads - in my cars one is orange and one is white. I believe that’s the same for ‘65. If either or both are grounded the system will pop fuses like a son of a gun. It also means that the correct sized _two pin_ bulbs must be used in all locations, specifically not the one pin bulbs that are the same sized. If there are single pin bulbs anywhere in the system a short will just carry on popping fuses. The bulbs are also plenty hot enough when lit to burn your fingertips. Not really blistering, but enough to take the fingerprint ridges off for a few days/week.
The first job is get the correct bulbs. And get a few spares. Next clean all the bulb sockets by sliding the wires up through the bulb base and giving them a quick scrub/wire brush/sanding with the abrasive of your choice. When you’re looking at the bulb sockets, look for melted wiring insulation nearby and for just plain broken wires which can ground against the frame and activate the lights even with the switches open. When you’re testing get a bunch of spare fuses to test the system as you repair it. You may get the problem fixed on the first go, but if not you’ll be glad you have a bunch of tries to get it right. It sounds like you have rear doors. If I recall they are powered from the ribbon cable that runs underneath the driver’s side of the front seat. The ribbon cable does a “T” under the rear seat and with that rear seat removed, you shoudl be able to see the white/orange wires which connect the bulbs to the switches.
Sweet. I'll look into it further. Thanks for all the help.
A bit off-topic but.... Tomorrow I'm getting new exhaust put on it. The current exhaust is a rusty single 2 1/4 and out of the muffler it goes down to 2 inch. Looks like a backfire bloated the muffler too. The new system will be 2 1/4 off the manifold, then expand to 2 1/2 into a stainless muffler. After the muffler it will have to go down to 2 1/4. The exhaust shop owner doubts he can bend 2 1/2 over the axle.
2 1/4 to 2 1/2 will be a good improvement. The ultimate for these cars was a factory dual system. But you need not just a special left exhaust manifold, but also a half-moon shaped column shifter to clear the second pipe. If you come across it and want it, go for it, but the single larger exhaust will work just fine for rpms in the normal range of 500-4500.
Perhaps your shop guy could buy a present 180° pipe in 2 1/2" diameter to save himself the pain of trying to bend one? And no judgment, but do you have confidence in the shop? Not too many really want to work on these old cars anymore, so not sure what your options are, but 2 1/2 all the way would be the best you can do.
From the factory these cars had both a muffler and a resonator mounted by the gas tank behind the rear axle. If you're heading for a factory style sound/solution, the resonator gives it a nice tone. Or save that for another day if you have better ways to spend the $$. Factory single exhausts exited out the passenger side, just to put it out there.
Dig around here under engines and exhaust and you'll find people who've posted opinions about Walker, Dynomax, and many other brands. Some have even posted videos you can listen to. For me, a 98 shouldn't be too loud and I wound up at more or less a factory dual system. I tried one of the louder brands and hated it within a day. I think I've got Walker brand on my car. Point is exhaust noise is on the personal taste end of things with these cars. And over the years I've become more interested in being quiet than being noisy.... But it's 100% your call and yours to enjoy anyway you like it.
As to off-topic, no hassle from me at all. Just a suggestion that you'll get more traffic and probably more help if you post exhaust under engines/exhaust and electrical under electrical and so on. There are people who are really interested in specific subsystems of these cars and 98's are pretty far afield in the car hobby, and even in the Olds hobby. Again, I'm completely happy to help here, but you'll be amazed at the depth of this crew when you really get 'em going with a specific question about a specific car.
You are so correct that nobody wants to work on this car. I wanted the windows ceramic tinted, the lightest tint possible with UV blocking. The tint shop said he's not interested. I asked him why not and he replied "too time-consuming". Later that day a took the car to a body shop that painted my 66 Chevelle many years ago. I wanted some paint work done and he said, "honestly, I'm not interested". I guess I'll have to tint the windows myself and do the minor paint work myself too.
I’m 61 and have been playing with these cars since the early 80’s. Here’s what I’ve seen:
1) At about 20 years, you can find cars getting turned in, so peak ‘66 Olds 98 parts availability was around 86-90. Somewhere in the late 90’s the ‘66 big cars (88’s, 98’s, Starfires) had pretty much cycled through the system and the self service junkyards were not really much worth more than 1-2 visits a year, even in rust free CA. And this was before EBay, so you had to be in a club or OCA, or whatever to source parts. eBay makes it a little easier these days, but those who’ve been holding specialist parts since then think of their hoard as their retirement and price the parts accordingly.
2) There’s a kind of bell curve to the car hobby with Mustangs, Chevelle, Camaros and select Mopars in the middle and all the other brands. The pony cars and A body GM’s are right in the middle of this popularity frequency curve. Plus foreign expensive cars for richer people per their preference. Olds 98s? They’re way, way out toward the edge of the curve, representing a minority level of interest at best. Mid-60’s GM/Ford/Chrysler boats have a following. It was always a smaller following than the more popular stuff and age is well on the way to shrinking their numbers. So these great big old cars are just are less popular, get less aftermarket support (if any) and you’ve got to really hunt for parts swappability from Cutlasses, 88’s and other year Oldsmobiles from 65-70. And then bet on parts that _may_ fit.
3) Since the knowledge is going away among professional shops - you’ve figured out that most older mechanics who knew these cars new are retired/retiring or gone, right? The new shop owners have to figure out if they want to do the work given current state of parts availability and the profit in the job. Then they have to have the young/middle age/older person who can do the work without burning huge amounts of shop time learning. Customers don’t want to pay for the less experienced people to learn how to fix these old cars, so it’s not always in the shop’s interest to take the job. Personally, I’m trying to get ahead of anticipated maintenance jobs like brakes, wheel bearings (front & rear) and other stuff before the knowledge goes completely “poof”.
4) The factory manuals of the day - do go get originals the ‘66 Olds Chassis Service Manual and The ‘66 Fisher Body Manual were great. But they assume it’s 1967 and you just order up new GM replacement parts from the regional depot. And they assume you have knowledge and some special tools to help you fix these cars. By 2025, many of those assumptions are not true. So you’re back to your own ingenuity and can use this site and team as support. You’re going to find offshore replacment parts that are reported to fit, don’t actually fit and that onshore NOS (new old stock) are getting more rare by the day. Take it in stride that maybe 20% of your purchases will be wasted from bad manufacturing, bad claims to fit or crap quality. I recommend USA made stuff for these cars, but sometimes the offshore simple stuff works just fine - like Wix oil filters and common stuff like that.
5) The experience of driving and riding in these cars was great, but it’s very different from the electronically controlled suspensions of today’s cars. The float was part of the experience. Road isolation and sloppy steering was designed in. They made due with tarpaper in the doors for water insulation. They’re great cars, don’t get me wrong, but they were made before computers were a thing in most businesses when slide rules won the day. They’re built to be repaired, not like the latter day plastic-fasteners we see in modern cars. But they’re still 60 years old. So with rose colored glasses, thoughtful safety prep (like a fire extinguisher & tools in the trunk) and a little nostalgia, you’ll have a ball.
And as you drive your car around enjoying the ridea, the history & all the improvements you make, here & there old people will stop and tell you about the Buick/Caddy/Olds/Chevy/Ford/Chrysler they remember, or a relative had, or other stories. It’ll be fun to connect with the nice people you might not otherwise share a word with. We need a bit more of that in this day & age, in my view. The other cool thing that happens is little, little kids of 4,5,6 years old have never seen a car like yours & their eyes go like saucers. Oh, and your kids may hate the car, but their friends won’t. Hahaha. Anyway drive it and enjoy!
Excellent post, all valid points. Thanks for sharing. Thankfully I can do 95 percent of the work myself and this car is intended to be a cruiser. Under previous ownership, it only saw 1026 miles in 16 years. I'll rack up more miles than that in just a few months.
Carry on cruising. Rack up them miles and have fun!
I tend to use my old cars around town on what would otherwise be very boring drives for groceries or dry cleaning or that kind of stuff. Even dump runs. Why not?
Olds built good stuff in those days and they can usually be repaired allowing for some patience, troubleshooting and sometimes money.
Hit us up here when something crops up that you didn’t expect, or don’t like. Myself excepted, the knowledge here about these machines is fantastic.
For about a year I've been waiting to install new front speakers in my 98 convertible. In the doors. And a little larger diameter than before. So it was project day. The speaker thing went fine.
Along the way I got a few shots I thought you might want to see when troubleshooting courtesy lights. Lesson 1 is the courtesy lights can be activated by the driver using the light switch or they will light up when the doors are opened. When any door is opened all door courtesy lights and any that might be under the dash should light up. But 60 years on sometimes the bulbs look like this with flattened out pin connections from _decades_ of use. Typical used courtesy light bulb. Flattened pins indicates age or perhaps heat and can cause inconsistent or no electrical connection
So get new bulbs, but be sure to avoid the single pin bulbs that look like this. They don't work in the 2 wire system: Typical GM peanut light, sometimes previous owners use these because they phycially fit, but they can cause shorts and otherwise misbehave. If you see t 2 wires at the bottom of the socket, don't shove this in and call it good.
The good part of this socket design is that the pins are spring loaded to maintain maximum contact with the bulb pins until they burn out. Great design. But you have to use the right bulbs.
Anyway just a quick note on what used ones look like, and bulbs you should remove from your car if they are in the wrong place.
