Reproduction Parts for 1916-1964 Chevrolet Passenger Cars & 1918-1987 Chevrolet & GMC Trucks
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I had to buy a new multitester because my 40 year old one was giving me fits with odd ball readings. I do have continuity to the gauges and the dash and the firewall.
With all new wires installed I am checking the system via continuity without power to confirm everything is connected properly before attaching a battery.
I am concerned that the headlight switch is bad. There is continuity to the park light wire no matter what position the switch is in. There is no continuity to the headlights no matter what position the switch is in. The dimmer appears to work but no continuity from the headlight switch to the dimmer regardless of switch position.
I do not relish taking this gauge out again to further work on it but if it has to be, it has to be. Are three replacements for these switches or can they be rebuilt if that is the issue?. I didn't see any replacements online but have not searched extensively.
Thanks
Rich
I guess the first thing I would check is to make sure you're using the correct terminals on the switch. Do you have a wiring diagram?
7046 old site posts
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1938 Master Business Coupe-Sold, now living in New Jersey
1953 210 Sedan
Tiny, I double checked them when I was assembling the dash. But I will do it again. I followed the diagram but maybe I need to check each terminal with the switch in different positions. It is possible I reversed the image and in that case the top and bottom terminal would be correct and the ones on the left really need to go right and vice versa. I hope thats all it is.
I just checked again and the switch is wired correctly. On my diagram the “S” terminal (11 0’clock) goes to the small light inside the headlight. I assume that is a marker light. That terminals has continuity to ground regardless of the position of the switch. I am testing terminal to ground and the end of the wire to ground. both are the same.
In the park position all of the terminals show continuity to ground except the “H” terminal (1 o’clock) and the “R” terminal (6 o’clock). They have no continuity to ground.
In the on position only the “s”terminal has continuity to ground.
Electrical problems are my Achilles heal. Am I testing this incorrectly? My multimeter is new and seems to be working correctly. The wiring diagram is attached with a mag view of the switch. I wired it just like the diagram shows.
My head light wires are just deadened for now. The headlight bar is off the car. the tail light is installed and wired. The dimmer switch and the brake light switch appear to be working, the horn button appears to make the correct contact as well. The dome light is installed the car.
Some of the wiring was damaged and spliced in many places. The harness under the dash was in decent shape and I followed that painstakingly as i disconnected and reconnected on wire at a time. Could there also be relays or other components that I am missing?
All things point to this switch as far as I can tell. But again electrical issue befuddle me.
Electricity makes my head hurt as well. You might peruse the old forums as well. I just did a search there for +headlight +switch in the 6-volt and 29-32 forums and came up with a lot of hits. Not all hits are specific to your quest but there's a lot of info there.
7046 old site posts
Save a life, adopt a senior shelter pet
There are many good people. If you can't find one, be one.
1938 Master Business Coupe-Sold, now living in New Jersey
1953 210 Sedan
Thanks Tiny, I will keep researching. I don’t know that I want to tackle this switch myself as it likely require some finesse. I am not really known for my finesse. I will also look for a replacement or a rebuilder.
I suspect the issue is mainly dirt and corrosion on the contacts. You can buy electrical switch cleaner. Google says you can also use isopropyl alcohol as a cleaning solvent. A good cleaning along with running the switch through a bunch of cycles (on-off, on-off a bunch of times) to wear any corrosion off internal contacts might turn things around. I've not had one apart but I suspect there's not a lot of moving parts to wear out inside the switch.
7046 old site posts
Save a life, adopt a senior shelter pet
There are many good people. If you can't find one, be one.
1938 Master Business Coupe-Sold, now living in New Jersey
1953 210 Sedan
Tiny, I’m a little afraid to take it apart for that reason. I have not had great luck rebuilding small electrical stuff. No matter how careful I am I always seem to have an issue. I don't think I can get cleaner in there without taking it apart.
There is a new development. As you said cycling the switch might help. I tried that last night and today I went out to do some documented testing. I drew 3 versions of the terminals on the back of the switch… on/off/park. I then tested each terminal to ground while my wife who is a really good helper as long as she doesn’t have to get dirty, documented which terminal were closed (continuity to ground) or open (no continuity) in each test. The result is everything seems to be working properly with one exception. The park light terminal is always closed. Meaning there is always power to that light.
The map light, horn and brake lights are also always closed, which I believe is correct. Headlights are only closed in the on position. Tail light and instrument lights are closed in the on and park position.
I tried to see if there was some cross stalk between the ammeter wire and the park wire but there appears to be some space between them. I was thinking if the contacts were touching that could be the issue. I will keep cycling the switch and hope for a solution. In the mean time I do have a battery disconnect switch that I will use to keep from burning the car up.
Thanks for all of your help. I really appreciate it as I learn more about this old girl.
Rich