Weird break light behavior

[dspeer]

I picked up my 1970 280 SEL about 3 weeks ago. When I drove it home, the break light stayed on permanently.

I brought it to my mechanic, who, among other things, adjusted the parking brakes and installed new pads on all 4 wheels. He inspected the master cylinder and found everything to be in good shape. According to him, all pads were very worn.

I've driven the car about 80 miles, and the brakes always felt good. No pulling to either side, no pumping necessary.

After I picked up the car, the break light was off at wirst, and then, 2 miles later, slowly came on again while using the brakes lightly, then stayed on.

Does anybody know what might be causing this?

Thanks!

Dietrich

[Mike D]

The brake light switch is pedal activated. It's either slid out of its mounting or has broken. Look on the shaft leading from the under dash pivot.

[ggenovez]

Don't the fluid sensors also activate the PBrake light indicating low fluid?

Check the brake rewservoir, and the sensors (if any ) and the wiring.

[Mike D]

Now see, that's what happens when you assume! I assumed he meant the brake lights and never even thought about the "brake" light.

If you are talking about the in-dash brake warning light then it is indeed fluid level activated. The little plastic floats inside the master cylinder are prone to developing leaks and causing the dash warning light to come on.

[Tomguy]

The little plastic floats also are prone to falling off of the sensors, causing this.

You can check your master fluid's level - both reservoirs should be filled appropriatley, you can unplug one (or both) of the level sensors and see if the light goes out. If so, you've found the bad sensor, and can leave it off if you like... Mine was unplugged for about 2 years before I found a replacement in a junker.

Keep in mind the front and rears are different lengths.

[dspeer]

Thanks for all those helpful answers!

I assume that the functionality of this also depends on the break fluid tank being completely level, correct? I haven't had the hood open since I got the car back, but if I remember it right it appeared to sit there at an angle.

[meltedpanda]

yes and no , the little floats are the key of they have fluid in them then they are no good, they sink and activate the light, disconnect and keep a good eye on your fluid level till you find replacement.