On the brake pedal itself.
the brake light switch is an air over elec. switch located in an air block on the floor behind steering shaft
There is no brake light switch. There is a brake light pressure censor that is located under the cab where the driver's seat is. T.R.
It's attached to the brake pedal arm.
Should be to the left of the clutch pedal.
You should check the air suspension switch, located on the passenger's side of the trunk. If the switch is off, the light will come on, also check the air suspension fuse. If both of these are OK, then the pump could possibly be going out.
The brake light switch is located on an aluminum air line junction block. The air line block is directly forward of the steering column on the cab side by the firewall. There is an access panel on the engine side of the firewall that gives you access for replacement.
Stuck brake light switch, or a short to power somewhere in the brake light circuit.
There's continuous power supplied to the circuit. When the switch contacts, it closes the circuit and allows the power to go to the brake lights.
It's just a weatherpack terminal. Literally a plug and play device.
There isn't a specific fuse for it... power is supplied to that circuit by existing fuses. You probably have a bad switch.
The brake light switch is located on a bracket behind the brake pedal support.