Hey fellas, Got a question. On a 51 Fleetline does the brake light switch itself need to be grounded or does it ground through the lights? Thanks for the help, the 'ol brain is working slow today. T
a brake light switch has power to one side, then when you push on the brake pedal the other side has power. nothing to do with any ground
They occasionally do go bad,check for power at the terminals,if you have power the current should flow through the switch when pressure is applied,have some one step on the pedal and see if it works,if it is bad,i heard you can just unscrew it and screw the new one in without having to bleed the brakes,just have the new one ready when you take the old one out,Cant promise this is right,but it is what I have heard.All the switch does is break the current until the contacts are forced to close. Harvey
if you remove the pressure switch from the system, you're going to need to bleed it... the only way a switch works is from direct hydraulic pressure from the master cylinder, and removing it will introduce air into a closed system, no matter how fast you think you can replace it
Thank you fellas, I have switched it out before, but this time, it's not working properly. It IS a mechanical switch that has nothing to do with the master cylinder, it screws onto the firewall and the brake pedal arm pushes the switch arm out. I was hoping it was a ground issue because if not, than it's back to the wiring...You know on these cars, it seems like if it's broken it always leads back to some random ground you had no idea existed T
Mechanical switch. No mater if it's grounded are not. If your having brake lite issues ground the tail lites housing are pigtail and see if it helps.
I tried re grounding the tail lights, nuthin for the brakes. The tail lights work with the headlights, the brake light switch had to be shimmed out a half inch from the firewall the other day in order to shut off when there was no pressure on the peddle. The worked for a day and then just stopped. I tried hooking up a new switch with no result and none of the wiring was touched. a bit confused. T
Take an ohm meter across the two terminals, have someone push down the pedal, see if continuity goes to zero. Another thought, is the brake arm on an eccentric and maybe shoes adjusted too tight?...possible you don't have enough travel in the pedal to allow the switch to close.
Dont discount the switch going bad even though you've changed it before. Make sure run a meter or light tester at the switch like AllSteel said.
also, My brake lights don't work until I work the turn signal left then right, the brake lights run through the turn signal(if 51 has one) and the contacts could become worn.
FiddyFour, you must be a "slow hand". I replaced one recently on my Buick and did not need to bleed. Ben
Come to think of it, I do have a turn signal that has not worked in a long time, It only had a few wires out of the 7 connected and the other day I pulled the whole damn thing out to finally get to the bottom of that problem. This is what is great about this site. It had not even crossed my mind that the few wires that were connected were running the brake lights... DUH I'll let you know what happens. Thanks T
Come to think of it, I do have a turn signal that has not worked in a long time, It only had a few wires out of the 7 connected and the other day I pulled the whole damn thing out to finally get to the bottom of that problem. This is what is great about this site. It had not even crossed my mind that the few wires that were connected were running the brake lights... DUH I'll let you know what happens. Thanks T
You said it was working before you shimmed the switch. After checking the wiring you removed, maybe check this as well. Just a thought, maybe a step above a w.a.g.
Take a piece of wire and jumper the two terminals of the brake switch. Make sure the wires are connected to the switch, or you can just take the two wires off and short them together. No brake lights, then it aint the switch.
OK just got back from the car, I will try to paint a better picture. My brake lights had been staying on unless I reached down and pulled the pedal back. To fix that I shimmed out the switch. The brake lights were working fine. I also have a guide 2006 turn signal that hasn't worked for a long time, only 3 of the 7 wires were ever connected. Because the original wire was faded, I have been unable to figure out which wires went where. So the other day, I cut the remaining wires of the turn signal and took it out to start that little project and about the same time, my brake lights stopped working. Here is where I stand, my taillights and headlights work, but no brake lights. I traced the wires from the brake switch and one runs to the headlight switch assembly and is bridged to another wire that runs into my headliner, the other runs straight from the brake switch to the headliner. There is one other wire that comes from my headliner and was at one time attached to my turn signal. I took a meter and when I hit the brake pedal the wire coming FROM the headliner lights up. So the question is, where should that live wire go if I'm bypassing the turn signal for now? I hope that painted a better picture for those who know their electrical systems. Thanks a million T
Seems you don't have a return spring on your pedal...once you get a return spring on, you can remove the shims. Do a search on Google (maybe here too) for your wiring...or if you have an ohm meter, you can get it figured out as well...I know I've seen the SS wiring posted before. Edit: I thought you mention Signal Stat
That mechanical stoplight sw. can be bench tested, before installing. When it comes to parts,..."New", only means "It's Shiny". 4TTRUK
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