guys,

I saw this today on my vehicle.
The brake lights stay ON even when Brake is not pressed. What's more bizarre was even after I disconnected the brake switch, the lights stated on.
When I measured the break switch input from the harness it read 6.5volts without brake switch activated. When i disconnected the brake switch, the brake sw input from harness still read 6.5v! No wonder my lights turned on. The light go through a flasher module which can turn on at 5v.

As soon as i cleaned off the dielectric grease in the brake connectors? The voltage dropped to 1v!

I have never heard or seen this behavior Before. Any inputs or suggestions ?

 

Find out where that voltage was coming from that it got through the dielectric grease, and assume the grease was not, "dielectric" after it got dirt and moisture in it.

I was thinking the brain has a pull up resistor that need to be grounded to show a brake switch being "on" but your verbiage clarified my answer.