Third Brake Light

[dentstew]

I put a new OEM Ford 3rd brake light (AL3Z-13A613-F) on my 2010 SCAB yesterday. Plugged in, fit perfect, screwed the light to the truck but did not reattach the headliner just to make sure it all worked. I got a mirror, propped it against the tailgate so I could see the lights and depressed the brake pedal. No brake lights were activated- nothing, no illumination at all. So I turned on my head lights and the red lights came on. I depressed the brake once more while the red lights were illuminated and they TURNED OFF.

Can anybody tell me what I need to do to get the lights to illuminate when I depress the brake pedal? I mean, come on, that is what a brake light is supposed to do, alert people that you are braking. Does this part not fit this truck even though Ford says it does and it looks like the original. Thanks.

 

[pat247]

I need to replace the 3rd brake light on my 2014 also. I have the connector to the red leds unplugged from the light itself to prevent it from shorting out when water gets in the light. I would start with that plug and look for corrosion on either of those two wires. It is possible that you just got a defective light from ford.

 

[B E N]

Are your other brake lights coming on?

 

[dentstew]

Yes Sir, the lower brake lights are working when the brake pedal is depressed.

 

[B E N]

Tough one. Do you have an aftermarket stereo or any aftermarket wiring that is run through the cab? You could bench test your old 3rd brake light. That would ensure that brake light is in fact bad, you can then test the new one. If it proves good you know there is some other gremlin.

 

[FordTechOne]

Did you only have this issue with the replacement, or was the previous lamp doing the same thing?

 

[dentstew]

As far as I know just this new one. When I went to have the truck inspected the technician said the 3rd brake light was not working so I purchased a new one. I just assumed (which I shouldn't do) that the lights were burned out. I will get it and try it and see. Thanks for suggestion.

Everything is original. No new stereo, no add-on lights, nothing. I will check fuses now. Though I don't think that will be a problem since I would think more than just this one brake light, when brake pedal depressed, would be acting up. But.....I am not mechanic. I never thought that the Hill Descent Control would be associated with a 3rd brake light either, so there you are.

 

[fordfreek]

I've replaced two of them, one on each raptor, and had no issues. Actually , one was replaced under warranty, and I just replaced one on my wife's truck. Almost sounds like maybe the wires weren't installed correctly in the pigtail on the light? Like the ground and the brake signal were swapped?

 

[FordTechOne]

The part number you obtained is correct per the Ford catalog. Stop lamp voltage comes in on Pin 3 and parking lamp voltage (small LEDs) comes in on Pin 5. Pin 1 is ground. I would recommend verifying whether there is 12V on Pin 3 with the brake applied and constant ground on Pin 1.

 

[dentstew]

I found out the problem. There was a wire into the harness (Plug) that had come loose and was not attached. The wire had come out and was loose back so far into the head liner that I could not see it until I got a high lumen light to shine into the space between head liner and roof. Once reattached everything got to working again.
Thank you for all the help. FordTechOne without you making your post I probably would not have looked for the wire and just kept banging my head against the wall.