Is it possible to connect this brake master cylinder wiring into my old wiring harness and back to my red brake warning light?
New brake master cylinder to old wiring
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This may have the information that you are looking for.
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T100 Non-ABS fluid sensor plug
So, when converting to disc brakes a lot of us use the T100 non-ABS master cylinder. We are then tasked with finding a plug to connect to the sensor that is in the side or out of the cap. Because the car runs without one connected a lot of us simply do without the function of the brake warning...
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It's an 11/71 the wiring is fine, I'm pretty sure the original connectors fell off though. And I can't seem to find any diagram that shows the correct color. I have 2 loose blue/red wires but the diagram shows green/white, which makes sense because the parking brake and brake light on the dash is green/white. And my original master cylinder only used 1 wire but this new one uses the black and white. Should I ground one?
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I was just going to snip the connector and put on these factory style bullet connectors I have a bunch of...This may have the information that you are looking for.
T100 Non-ABS fluid sensor plug
So, when converting to disc brakes a lot of us use the T100 non-ABS master cylinder. We are then tasked with finding a plug to connect to the sensor that is in the side or out of the cap. Because the car runs without one connected a lot of us simply do without the function of the brake warning...
that's the WRONG answer there ............
you NEVER snip a factory connector , period !
The early brake light works like this
The two pressure switches are normally closed with no pressure on them. They monitor pressure in the MC. They provide a ground to the brake warning light via the GW wire. The light is held off by the brake pedal switch (open with no foot on brake.) So when you mash the brake pedal, the brake pedal switch closes (turning on brake lights), and turning on red brake warning light if there isn't sufficient pressure in the MC.
The brake pedal switch has two contacts in it, one side feeds the brake lights, the other feeds the brake warning light.
The two pressure switches are normally closed with no pressure on them. They monitor pressure in the MC. They provide a ground to the brake warning light via the GW wire. The light is held off by the brake pedal switch (open with no foot on brake.) So when you mash the brake pedal, the brake pedal switch closes (turning on brake lights), and turning on red brake warning light if there isn't sufficient pressure in the MC.
The brake pedal switch has two contacts in it, one side feeds the brake lights, the other feeds the brake warning light.
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I have the later cap in my 73. You could wire the GW wire that went to the old pressure switches to the new cap, provide a ground to the other cap wire, then jumper the brake pedal switch (the side that feeds the warning light). So when you get a low level, the cap switch closes and grounds the warning light, turning it on. Use at your own risk.
