Denm33

I have a 1964 olds cutlass Holiday coupe.

The courtesy light does not work--either when you open the doors or when you turn the light switch to the left. I have tried to manually grounded the door switches. That did not work, so that tells me that the switches are fine.

Any tips here guys?

That fuse runs the brake lights, clock, and courtesy lights. The brake lights work fine. I was wondering if maybe the clock has something to do with it, the clock has been inoperable for many years. (In the time I have owned the car the clock nor the coutesy lights have worked.

I know the bulbs and sockets are fine.

Thanks for any tips.

Oldsguy

The wiring would be a good bet. There is probably one wire from the fuse panel to the courtesy lamp, then to all the switches. If that first wire is open, no lights even if the switches work. Do you have a volt/ohmeter? You really need one and a service manual to know for sure what you are looking for and where.

Edit: I just got home and checked the wiring diagram for the 1969 year model Oldsmobiles. Orange was used for the 12 volts to all accessories, cigar lighters, lamps, etc. In that year the 12 volts was wired to all lamps and accessories first, then switched to ground with their respective switches so you can isolate part of the bad wiring if for instance, the cigar lighter works and the map light works but the lamps do not. Orange may not be the color used in 1964 but if you can find the color on the courtesy lamp that should give you something to follow. I have a strong suspicion that you car will be wired similarly. One more thing, if you have no blown fuses, you have an open wire that is not shorted to ground, it may have been pinched or more than likely corroded over time.

rocketraider

Is this the overhead dome lamps, the underdash courtesy lamps, or both?

The CSM wiring diagram shows three feeds on the load side of the STOP-DOME fuse. One to the clock that incorporates its own 2A fuse (though my guess is the clock's points are burned), one to the underdash courtesy lamps, and one that feeds both the dome lamp and brakelight switch. All ORANGE wires.

The dome and courtesy lamps share a common ground thru either the door jamb switches or the headlight switch, though it's kinda odd that neither works. Especially since the ground path for the courtesy lights is separate from the dome light and doesn't go thru either of the body wiring connectors. If they all went thru that, you could test for bad connection there.

You say you know the sockets are fine. Have you used a voltmeter or test light to probe the ORANGE wire for 12V at all sockets? They can look fine and still be wacked.

Bulbs- you're using a double contact bulb in the underdash lights? think they're supposed to use a 90. Sailpanel and console lights too if equipped.

Next step is to test the WHITE ground wire for continuity at the headlight and door jamb switches. Also make sure someone hasn't put a big car H/L switch in there. They're identical except the F85 has the dome light switch, the big car doesn't.

The WD is showing a 4-wire splice in the ground harness, but even if that had completely come apart or corroded, the underdash lamps should still be able to ground thru one of the door switches.

Have you popped the door jamb switches out to visual check or clean them? WD-40 can do amazing things here. After 44 years you may have some unseen corrosion between the switches and the car body.

You may have to pull the fuse block and check behind it to make sure all three feeds are still connected to the load side fuse clip.

I recommend buying the 1964 service manual set. It has color wiring diagrams and invaluable service info. Get the 5-volume paper version as I hear the diagrams on the CD version are kinda poor quality.

Good luck.

Denm33

Thanks so much for your advice. I have answered your questions in Italics. I know I am going to have some other questions soon. Thank you thank you

Is this the overhead dome lamps, the underdash courtesy lamps, or both?
Mine just has the courtesy lights in the sail panels. No dome or under dash lights.


The CSM wiring diagram shows three feeds on the load side of the STOP-DOME fuse. One to the clock that incorporates its own 2A fuse (though my guess is the clock's points are burned), one to the underdash courtesy lamps, and one that feeds both the dome lamp and brakelight switch. All ORANGE wires.

The dome and courtesy lamps share a common ground thru either the door jamb switches or the headlight switch, though it's kinda odd that neither works. Especially since the ground path for the courtesy lights is separate from the dome light and doesn't go thru either of the body wiring connectors. If they all went thru that, you could test for bad connection there.
OK--I will check that and give the headlight switch a once-over too

You say you know the sockets are fine. Have you used a voltmeter or test light to probe the ORANGE wire for 12V at all sockets? They can look fine and still be wacked.
Yes they are reading 12v, the white is 0v. A question, if the white one was working properly, whould I get a 12v reading on that?

Bulbs- you're using a double contact bulb in the underdash lights? think they're supposed to use a 90. Sailpanel and console lights too if equipped.
Yes I am using double contact bulbs

Next step is to test the WHITE ground wire for continuity at the headlight and door jamb switches. Also make sure someone hasn't put a big car H/L switch in there. They're identical except the F85 has the dome light switch, the big car doesn't.

The car is 100% original, I am the second owner. I don't think anything has ever been removed from it.

The WD is showing a 4-wire splice in the ground harness, but even if that had completely come apart or corroded, the underdash lamps should still be able to ground thru one of the door switches.

Have you popped the door jamb switches out to visual check or clean them? WD-40 can do amazing things here. After 44 years you may have some unseen corrosion between the switches and the car body.
yes I have popped them both out and tested them, they are working.

You may have to pull the fuse block and check behind it to make sure all three feeds are still connected to the load side fuse clip.
Yes I did that. All looked fine.

I recommend buying the 1964 service manual set. It has color wiring diagrams and invaluable service info. Get the 5-volume paper version as I hear the diagrams on the CD version are kinda poor quality.
I have the old paper books. They do have color diagrams. I'll take another look there.



Good luck.
__________________
I know absolutely nothing about Oldsmobiles.
Just ask the owner of Oldspower.com

rocketraider

Umph- this one's a stumper. The problem HAS to be on the ground side since you have 12v on the orange feed wires.

Time for continuity checks. With battery disconnected, use a continuity tester (sometimes called self-powered test light, these have a battery and they are designed to send a voltage thru the wire. If tester lights, wire is good. If not, wire is open.) With the doors open so the switches will make the ground path, probe the white wire contact in the sockets. Then touch the other side of the tester to ground and see if the tester lights.

If it doesn't light, pop out the jamb switches and touch the test lead to the white wire in those. If tester still doesn't light, there has to be an open wire in the WHITE ground circuit. That may be fun to find.

Just for grins, look underdash and see if you can find any wiring for underdash courtesy lamps. The pigtails were usually there even if car didn't have them factory installed. Olds sold a lot of them thru dealer parts counter.

Wish I could be more help, but this is all I can think of. My dome light problems always worked the other way, as in wouldn't go off. I had a 76 Custom Cruiser wagon that they wouldn't go off, and I finally traced it to a bad rear door lighter socket. Somehow, who knows how, if the lighter was in the well, it created enough ground path that the dome lights wouldn't go off. Take the lighter out, everything worked fine. I finally unplugged that lighter well and taped the wires.