|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
11-08-2020, 10:41 AM | #1 |
Senior Member
Join Date: Sep 2020
Location: Syracuse, NY
Posts: 173
|
Brake Light Question
My first issue is no brake lights. I went under the car and saw this switch pictured. It appears to be a normally closed switch, and when pressure is exerted it comes open. So when installed, I can see that the plunger spring is compressed, presuming that is causing an open circuit, and when the brake is applied, the plunger is released, and closes the circuit allowing voltage to flow to the brake lights.
My question is when should I see 6V on the switch? Does the ignition have to be on for power to go to the brake lights? I'm not seeing with ignition on or off, so I may have to investigate further. Is there a common wiring point I need to research? I know I'm going to have to purchase a Model A manual, but I was looking at hints to try to be able to get a starting point so at least I can take this for a ride safely - and not get rear ended on a Maiden Voyage. Thanks in advance for replies. |
11-08-2020, 11:16 AM | #2 |
Senior Member
Join Date: May 2010
Location: So Cal
Posts: 8,753
|
Re: Brake Light Question
There should be 6V to the brake light switch at all times.
The ignition switch only controls the ground path from the points to the coil. |
Sponsored Links (Register now to hide all advertisements) |
|
11-08-2020, 03:19 PM | #3 |
Senior Member
Join Date: Jun 2014
Location: Land of Lincoln
Posts: 3,131
|
Re: Brake Light Question
The brake switch ok to be a cheap repo part, it doesn't have the brass bushing where the plunger comes through, remove and check it out and or buy a switch that has the brass bushings
__________________
Don't force it with a little hammer tap, tap, tap get a bigger hammer tap done |
11-08-2020, 04:22 PM | #4 |
Senior Member
Join Date: May 2010
Location: Largo Florida
Posts: 7,225
|
Re: Brake Light Question
As said, the switch should have power at all times and the repro's tend to be junk.
So we don't yet know if the switch is bad or not, time will tell. The switches can usually be fixed. |
11-08-2020, 04:30 PM | #5 |
Senior Member
Join Date: Apr 2015
Location: Boise, Idaho
Posts: 1,578
|
Re: Brake Light Question
Here is the inside of a possibly original (dirty!) H.A. Douglas Mfg. switch.
Just a couple of contacts that are normally closed when the switch is at rest. Installed the switch is held open, and pushing the brake pedal allows the plunger to close the contacts. Last picture shows the brass bushing....
__________________
Early '29 CCPU that had a 4-speed, but not any more.......in the family since '62 |
11-08-2020, 06:53 PM | #6 |
Senior Member
Join Date: Sep 2020
Location: Syracuse, NY
Posts: 173
|
Re: Brake Light Question
Sponsored Links (Register now to hide all advertisements)
I then started the same sequence for the Passenger side light. Corroded connections, oxidized socket, and a bulb that had an open in the base - not the filament. The scavenger hunt began trying to find a 6V bulb, with no success(multiple auto parts store, and even a Tractor Supply). I'll have to go online and purchase multiple of each as I now see I'll need to main inventory locally for this 90 year beauty. I was considering doing soldering and shrink wrap to eliminate the multiple connectors as well as source of trouble. Please let me know if I'm heading down the right route before I do so. Again, thanks for the great assistance! |
11-08-2020, 07:33 PM | #7 |
Senior Member
Join Date: May 2010
Location: Largo Florida
Posts: 7,225
|
Re: Brake Light Question
OH, I thought you didn't have power to the switch.
If bulbs or other such things aren't found locally, they can got at one of the 'A' vendors such as Bratton's, Snyders, etc. I'm a big fan of soldered and shrink tube joints. I try to slide them in a woven period type loom or then wrap with old friction tape. |
11-08-2020, 10:07 PM | #8 |
Senior Member
Join Date: Sep 2020
Location: Syracuse, NY
Posts: 173
|
Re: Brake Light Question
Thanks - I'll pursue the method you mentioned for a more permanent solution.
Regarding the power - my meter wasn't reading properly due to the bad grounding point - one of my first issues. Once I resolved this, and the information here was given, all the other pieces were fortunately sequential. |
11-09-2020, 11:34 AM | #9 | |
Senior Member
Join Date: May 2010
Location: Largo Florida
Posts: 7,225
|
Re: Brake Light Question
Quote:
Ah, those pesky intermittent grounds. Another one of life's little wonderments. |
|
11-09-2020, 04:14 PM | #10 | |
Senior Member
Join Date: Jul 2011
Location: Redondo Beach, CA
Posts: 5,849
|
Re: Brake Light Question
Quote:
Once you have your connections clean, apply some di-electric grease to the connections and light sockets to keep moisture out. Put a dab on your ground connections also. JMO... |
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|