Electrical issue, any ideas?

[Pat Marshall]

After a car show last weekend, I put my car away. When I went to start it a couple days later the battery was almost dead. So, I recharged the battery, I restarted the car and noticed that the lights were flickering, not at a regular pace like a turn-signal pattern, but in an irregular pattern. Also, down low in the dashboard in the lower steering column area there is a slight bonging sound when the lights flicker.

It is NOT the sound that the light flasher makes.

Before I go tearing stuff apart, I'm wondering if any one has had a similar experience?

[Milsteads Garage]

A voltage regulator with stuck contacts will cause the lights to flicker and also will cause a parasitic drain when they fail a certain way. The sound under the dash I am not sure what it could be. Check the charging output with a fully charged battery and a multi meter. If the voltage is reading abnormally high this is your issue.

[Barry Wolk]

Sound like an automatic circuit breaker somewhere that's actually doing its job. Every window and seat function has one that opens on overload, cools down and repeats until you have a dead battery. Be glad you're hearing that. Now you should be able to home in on the sound. These circuit breakers can be problematic as they are easily bypassed by moving the black wire from on terminal to the other. Then you have no protection.

It could also be stuck clock. When they stick the motor becomes a small heating element.

[Pat Marshall]

Thanks, guys!

The clock is running great!

I think the sound is coming from the driver's door. However, my ears were victims of naval gunnery, so I'll have my all-hearing wife check it out in the morning!

[Pat Marshall]

This morning, my wife listened and she believes the sound is coming from behind the driver's side kick panel. I'm going to start pulling stuff off. I believe the are no circuit breakers behind that panel, anyone know where the closest one to that panel is?

[Pat Marshall]

UPDATE! I REALLY stuck my head down there. The sound is coming out of the door air duct (and it's broadcasting into the footwell)! It's the window circuit breaker! So, I'll take the door panel off. Suggestions/instructions are welcome.

[Barry Wolk]

I'd look at the switches for the seat and window before the breaker. One could be engaging a relay with a stuck switch. I believe there are two circuit breakers mounted to a plate on the drivers side. The windows and seat are always on. For testing you can disconnect the battery pull the switch banks into the passenger compartment without having to disassemble the door panel

For those that may not know, an automatic circuit breaker reacts to an overload, which can be a short circuit to ground, or it can be a stuck switch trying to open or close a window or move a seat at the end of its travel. The breaker will overload, opening a bimetal switch. The noise you hear is the breaker opening and closing as the bimetal cools. There is no fuse on these circuits so the result is a dead battery.

[Pat Marshall]

I'd look at the switches for the seat and window before the breaker. One could be engaging a relay with a stuck switch. I believe there are two circuit breakers mounted to a plate on the drivers side. The windows and seat are always on. For testing you can disconnect the battery pull the switch banks into the passenger compartment without having to disassemble the door panel

For those that may not know, an automatic circuit breaker reacts to an overload, which can be a short circuit to ground, or it can be a stuck switch trying to open or close a window or move a seat at the end of its travel. The breaker will overload, opening a bimetal switch. The noise you hear is the breaker opening and closing as the bimetal cools. There is no fuse on these circuits so the result is a dead battery.

As always, thank you, Barry. All switches appear to be working correctly and the motors are opearating smoothly, but the relay noise keeps on going. The sound appears to be coming from behind the plate direclty below the vent window.

Ss you can see, I already pulled the door panel. Tomorrow, I'll pull the plate and see if I can find something. Not sure what to do when I get in there...

31951

[Roger Zimmermann]

After so many years, the wiring can act in a strange fashion. When I was in the process to sell my '57 Eldorado Brougham, I noticed that by lowering the passenger front window, the vent vindow opened too. By closing that door's window, the vent window opened more.
Finally, I opened the wiring going to the door and found that the insulation at the flex point broke and 3 wires were without insulation for a short distance.

31952

[Barry Wolk]

Roger is 100% correct that the door harness could be a likely candidate. The Mark II gas tank access has some special wire to allow for flex. It's a tiny wire in thick insulation. I believe the door harness may use the same wire. It's meant to hold up, but it doesn't. I had to fix mine without using solder as solder creeps along the copper wire making it quite rigid, causing an early failure.

Pat, also note that the hinges are an unreliable ground for the door so they provide a separate black wire that runs from the terminal on the circuit breaker that attaches to the plate. When you remove the plate from the door anything, like the door lights and cigar lighters, lose their reliable ground. I did two things to resolve this. I made a black jumper wire from the plate to the door so the relays and circuit breaker would always have a reliable ground. Also, I moved the ground from the terminal block and moved into a bared surface near-by. As an 18-year old electrical apprentice I found that many machines using low-voltage controls used the body of the machine as a ground, like a car. The very first lesson was in how to create a reliable ground path that eliminated the possibility of the threads of the screws being used to carry current. The crimp rings and forks had to attach directly to the cleaned ground surface and held in place by the threads. Steel screws should not carry current because they have a lower current-carrying capacity.

[Barry Wolk]

I took a closer look at your photo and it appears that your front window switches don't appear to be self-centering, which can activate a relay coil, but have no power to move the window. There's a control circuit and a power circuit in each switch. That would account for a battery drain and a sound, but it may not be the circuit breaker you're hearing.

This is a new one on me.

One last thought. Check where the black wires come from on that plate. Only the wire from the harness should go to the grounded side of the circuit breakers. The other stud is for ground wires from motors, lights and lighters. Mounting any of them on the wrong stud leaves the circuit protection defeated. The black wires can easily be confused. Doing it wrong can easily cause a fire. Normally you think of circuit breakers that open the hot wire, but on a car switching is how the circuit accesses a ground.

[Pat Marshall]

I took the lower driver's door panel off and it turns out everything in the door was OK, and it seems the sound was coming the other way through the drivers kick panel ducting into into the air duct at the bottom of the door and up into the door. It was very illusive. I was thinking the sound was coming from a relay, but since there are no relays under the dash, that wasn't it.

The sound was omnipresent - it could be heard in the driver's door, in the engine compartment (like it was coming from the brake booster area) in the driver's footwell where it seemed the sound was coming from everywhere.

The only thing left was looking for the problem below the dashboard!

We got lucky! After I put the lower door panel back on, I took the underdash plate between the steering column and the driver's kick panel off. There was no arcing or other evidence of problems, except that darned sound, which was really loud after the plate was removed. Next my long-armed son, Dave, reached under and started feeling around, and when he touched the light switch he felt that it was vibrating heavily in concert with all the dimming and flickering of the car lights.

Dave disconnected the light switch - the symptoms went away! I immediately ordered a new switch from Dennis Carpenter.

The switch will be here in a couple days, so we'll find out if it actually was the switch, or the switch was reacting to an issue elsewhere. However, I now remember just before the problem started I was having trouble getting the switch to properly control the light level in the dash pod dials.

In the meantime, we taped off the electrical wires and stuck the old switch back in. It looks like it never happened, and I'll be off to a car show tomorrow. I just can't drive at night for a few days.

I'll give a report in a few days!

Thanks for everyone's responses!

[tluke]

So I've had this type of issue twice, on separate cars, both '55 Cadillacs so this may not apply but in both cases it was the thermal breaker in the headlight switch that kept tripping due to shorts in wiring elsewhere. I've never had the headlight switch out on my Mark II but if there is a thermal breaker that could be the cause of the sound, but not the cause of the issue. In one case there was an intermittent short in the wiring to the headlights that was grounding out and tripping the switch's thermal breaker, flashing the headlights and clicking. The breaker would cool down once tripped and reconnect briefly then the short would trip it again. Each time there was a click made by the breaker opening and closing (vibrating). On the other car it was a short in a wire to the rear clock (limo). On that car the body wiring for interior lights/clocks etc. came straight off the headlight switch so every time the clock rewound it would trip the thermal breaker in the headlight switch and if the headlights were on, they'd go out then come back on in a few seconds. That was tougher to resolve. Before finding it I cleaned the contacts on the breaker which was a good idea anytime the switch is out. Later model Cads that year put in a fuse in the body wiring circuit that would blow first and prevent tripping the headlight switch for anything but a short to the headlights themselves. Hopefully it was just a short in the headlight switch itself, maybe the rheostat shorted out causing the issue with dimming the instrument lights mentioned.