I have a 2020 XL F-150 5.0 4X4 and some of the (minor) mods I've made are:

-Hardwired tailgate LED strip to trailer harness
-Replaced license plate lights with LEDs
-Replaced third brake lights with LEDs

I've always noticed that since owning my truck (bought it brand new back in May/June of this year) whenever I would lock/unlock from the key fob, it would take multiple presses for it to register with the truck. So when I took it into the dealership, they said it was the BCM and replaced it. Dealership stated they were having trouble pairing the BCM with the tire pressure sensors because of the third brake light LEDs because it was expecting a certain output / wattage and the BCM was causing the door lock to fail. So some immediate follow-up questions I have are:

Is there an LED that matches OEM wattage so bypass the BCM?
If not, is forscan the only way to bypass that?
If I plan on replacing the OEM Headlight housing and they have LEDs, will I experience the same problem that I am having now? For the record, looking at getting the Morimoto Hybrids or the AlphaRex PRO and getting LEDs for the bulbs.

Any insight is appreciated, thanks!

 

My guess is your getting interference from the led's. Swap them back to bulbs or just remove them and see if your trouble goes away. Forscan isn't going to help with the 3rd brake light.

 

Yeah, that's what I've had to do to alleviate the problem. It's unfortunate but it is what it is. Will i also see this issue in replacing the headlight housing?

 

You may or may not. Depends on the amount of RFI the new housing produces. Also, the headlamps are a long way away from the RTM which receives the TPMS signals and is mounted in the roof close to the HMSL.

Problems with aftermarket LED HMSLs are well documented in the forum.

 

Probably not, search the forums, your not the first to use those headlights. The secret with the aftermarket led's is to stay away from the cheap ones.

 

Isn't the keyfob antenna in the interior near the 3rd brake light? Probably why it is so suceptible to interference from LED bulb swaps in that location.

Switch to an OEM LED 3rd brake light instead?

 

Yes, on Crew Cabs it is mounted above the rear passenger door. The RTM receives RKE transmissions as well as TPMS transmissions.

 

I switched my third brake light and rear cab lights to LED never had an issue. As another poster said the leds your using are probably causing an interference issue

 

I would try some better Canbus LEDs. I swapped cheap LEDs into the CHMSL and cab lights shortly after I bought my 2015. I have never had any problems, but now purchase Canbus LEDs instead of the cheapies.