Brake lights wont shut off in my 91 chevy k1500

Check your cluster connector for loose or damage pins Inside your connector good luck

Check your Brake Switch on the Back of your Brake Pedal, you have loose wires or your switch is not working properly

Sounds like a wire is shorting out. Trace it back and see if there's a bare spot touching metal. Hope that works

As far as the brake, your brake switch button may be stuck. It is above the brake pedal and looks like a chrome cylinder. There is a button on the end. See if you can get it loose. As far as the oil guage, the sending unit may be defective, Make sure the oil level is good in the engine.

on the top of the transfercase on the drivers side there is a vacuum operted switch check and replace if needed

Have you checked the fuel pressure?

Sounds like you have a bad connection at the light housing. If you have a volt meter check the voltage at the bulb connector when the brakes are applied. You may have a bad wire coming in at the housing. If you do, the connector can be changed.

could be the brake switch under the brake petal if it sticks they wont work or could be a fuse

try disconnecting the negative battery cable for ten minutes to reset the computer.

good luck

Pulsing of Brake Pedal is Usualy Caused by Rotor RUNOUT Meaning Hot Spot on Rotor -<a thicker spot on rotor , The FIX is replacing rotors