Third Brake Light Will Not Turn OFF
The red light on the back cab wont go out, after I exit the truck.
First, the red light on the back of your cab is the third brake light. Are your rear brake lights also staying on ? If so, it sounds like your brake pedal switch is either not working or is out of adjustment. If there is no adjustment on the switch itself then your brake pedal return spring is broken / missing and not pulling your brake pedal far enough to engage the switch and turn off your brake lights. A quick test of this is to pull up on your brake pedal while you have someone watching your brake lights. If they turn off when you pull up on the pedal then you need to fix the spring issue. If not, then you could try to disconnect the brake switch electrical connector and see if the lights go out -- I believe the switch is normally CLOSED ( when the switch is not being pressed, the contacts are closed and the lights are on ) so, with the switch wires unplugged, the lights should be off ( because the "switch" is now technically OPEN ). If the lights turn off correctly with the switch disconnected and the pedal return isn't an issue then the switch itself is faulty. The second part of your question is pretty easy also. Press the lock button on your key fob and HOLD it down until you hear your horn beep once. now, every time you press your lock button it will lock the doors, pressing it again ( in quick succession ) will cause the lights to flash and horn will beep. Hope this helps.
One More Solution:
You have to press the lock and unlock button together until the horn honks to reset the honking on lock feature. the brake switch is adjustable but if it's on up there the other ones will also be on if they're not burned out. the cargo light is also up there and bulbs may have been switched or there's a wiring issue.