Hey guys. Alright so I have an 05 f150 and when ever I press the break pedal my lights do not turn on. When I turn on my headlights they come on but not when I press the break either. They randomly will engage when im releasing the break but not at full brightness. Its almost like they are not getting a full 12V.

If anyone has any suggestions on what to do or maybe whats wrong that would be nice.

I also just put on the Viper 5901 alarm. Will this maybe have anything to do with them not always turning on when I break??

 

Maybe the Brake Pedal Position Switch has come loose. It's the lower plunger type switch that is operated by the pedal.

 

Ya thats maybe what I thought I read other posts but their break lights were not working at all. Mine kinda have a mind of their own. I will definitely check that later today though. Thanks

 

buy a cheap volt meter and test the the bulb connection while someone presses the brake. if that doesn't work test the switch. if that doesn't jump whatever portion of the circuit may be going into your alarm in order to rule that out as a cause