08 F150 SXT. tail lights stay on weather pedal is pressed or not. i checked the switch on the pedal.looks ok. replaced the multi function switch. worked for bout a week. checked fuses 1 bad (run/accessory -wipers, instrument cluster, & audio for stx). right rear turn bulb is blown.

 

I am assuming you replaced the blown bulb? And by taillights I am assuming you mean brakelights. You have turn/brakelights and then you also have taillights/marker lights.

By chance are you running LED light bulbs?

 

Do you have a trailer brake controller?

 

no brake controler and no leds.changed bulbs . turn signal on passager side still don't work. just found out the 3rd break light don't work at all.

 

Sounds like you have a bad spot in your wiring harness. has the wiring been modified for any reason?

 

Is the vehicle new to you? Sounds like the wiring was modified for previous owner if the truck is new to you. Maybe a remote start or ???? who knows.

 

I,ve had the truck bout 18 months found out later it was leased .ever get your truck back from a dealship & it was worst than what it was. things are going wronge that shouldn't.

 

The wire for the third brakelight comes directly from the brake pedal switch. It's lightgreen(at least it was on the earlier trucks). I don't know if Autozone has diagrams for your year truck or not.

 

i'll check that out thnx

 

there was a chip spliced into the MAF sensor. i took it out wire nut everything togetthere. Ford wants too much for a new. it should get replaced