The brake lights on my 2004 F-150 heritage stopped working. I got to looking at the brake pedal switch on the brake arm. When I push the switch up (with my fingers)the lights come on. The switch is functional, its just not being manipulated when the brake is depressed. Does this sound like the problem to you guys? On a side note my blinkers will sometimes stay on, not blink just stay lit. The turn signals started acting up awhile before my brake lights went out. Could the brake switch be causing that problem too? Any suggestions? Thanks fellas.

 

If the truck will shift out of Park after starting, it is not an issue with the Brake Pedal Position Switch, the same circuit is also the shift interlock switch on the '04 Heritage ( same as the 97-03 MY ).

Try tilting the steering wheel all the way up, and retest.

Some times the MFS ( MultiFunction Switch ) connector will start to pull apart, and this is one of the symptoms that will happen.

If this fixes the issue, pull the knee panel, and check the MFS connector pins for corrosion / discoloration



If this is the case, clean the pins, put the connector back together, and pull up some slack from the harness towards the truck ( vs. towards the MFS ) and zip tie it to the metal knee panel frame, so it cannot pull apart again.

 

My truck is a manual and I don't have tilt steering, sorry I should have mentioned that.

 

Ok, you are going to have to skip the test, and just tear into it and check then.
That is really just a time saving step some times.

 

Ok thanks SSCULLY, so your recommendation is still the MFS or the brake pedal switch? Is replacing it the only way to test if its faulty or not?

 

The MFS connector is still the place to start.

 

The explanation for your diagnosis of the MFS was not having the ability to shift out of park. Since I don't have an automatic, I.E. don't have to depress the brake to shift out of park, I wasn't clear if your advice was relevant or if a new diagnosis could be given.

 

Good point, I focused on the non tilt only with the problem. I am looking at the Stop / Turn EVTM cell, the CPP ( Clutch Pedal Position ) switch is in the trans control cell.
Good thing you hit me up along side the head with the manual again

Once more, so it sinks in Non Tilt, MANUAL trans.
Ok, I think I got it now ( just keep an eye on me, dad had to hit me up along side the head more than once for the same thing... ).

At the BPP switch, use a meter on the contact.

The White w/ Yellow stripe wire is from fuse 15 ( cab fuse panel ).
When you press the brake pedal as normal, the REd w/ Light green wire should have power.

While you are down there, take a look at the MFS connector.

This still leads me to the MFS or the MFS connector, but the easy test is the meter with the BPP.