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Key Fobs and LED interference

Damn this has me worried now, I just upgraded my 3rd brake and cargo lights to the diode dynamics LED about a week ago, so far no problem, did you have the issue immediately or did it suddenly start happening after a while?
Mine started 4-5 days after install. It started as an intermittent problem but now it's every time I start the truck :rolleyes:
I have had the diode dynamics for the reverse lights/cargo lights but not the brake light (CHMSL) for some time, no issues, $85.75 cost with shp and a discount.
Cargo Light LEDs for 2011-2020 Ram 1500/2500/3500 (pair)

SKU: DD0394P

ColorCool White (6000K)Bulb ModelXPR (720 lumens)
The brake light is probably my problem then because that's what I did. Makes me ticked after I spent too much on it but oh well. Now the challenge will be finding a brake light that works. Drives me nuts having one incandescent bulb on the whole truck.
 
Mine started 4-5 days after install. It started as an intermittent problem but now it's every time I start the truck :rolleyes:

The brake light is probably my problem then because that's what I did. Makes me ticked after I spent too much on it but oh well. Now the challenge will be finding a brake light that works. Drives me nuts having one incandescent bulb on the whole truck.
Why would an incandescent bulb cause interference with fob? I thought inferior LEDs were to blame.
 
Lasfit. They redesigned the original one just for this reason.


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Do you happen by chance have the link to the bulb from Lasfit? I looked on their site and could not find it there. Thanks
 
Do you happen by chance have the link to the bulb from Lasfit? I looked on their site and could not find it there. Thanks
I had to search for 2020 Ram instead of 2022 like mine. It came up then. There's a message on the product saying it doesn't work with 2021 models. But there's reviews from owners of 2021s saying how great it is. So I decided to try it. Should be here in a few days.
 
Lasfit. They redesigned the original one just for this reason.


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I had the original LasFit LED bulbs with no problem but had 2 of the die on me in just over a year (in addition to a couple in the cab).

I was going to switch but to keep the same hue of the lights in the cab (everything else was LasFit) I went with more LasFit bulbs to replace the burnt out ones. The "new" design bulbs in the CHSML (all 3) are working great and no interference.

Do you happen by chance have the link to the bulb from Lasfit? I looked on their site and could not find it there. Thanks
Main page:

These are what I originally put in the CHSML:


This is what I have now:



This newer version says it's only for 2019 and 2020 trucks so I'm not sure what the issue is with them.

FWIW I did not have any interference issues with the "older version" (flat) or the "newer version" (round/barrel).
 
So I put the diode dynamic cargo bulbs in and everything worked perfect for ~2wks. Now I'm having issue again being able to lock door with the door handle button and occasionally getting the "no fob detected" message. Pretty frustrated. You'd expect something this simple should just work like every other vehicle I've had. what gives?
 
So I put the diode dynamic cargo bulbs in and everything worked perfect for ~2wks. Now I'm having issue again being able to lock door with the door handle button and occasionally getting the "no fob detected" message. Pretty frustrated. You'd expect something this simple should just work like every other vehicle I've had. what gives?
Interference. Whether it's radio frequencies or some other invisible magic beams it's having a hard time sensing the fob (I think the hub is in the roof near the CHSML).

With all the technology these days, especially wireless, the air would be thick with it if you could see everything that's going on.

The truck is designed a certain way. Wire bundles, antennas, and shielding are installed to maximize signal connectivity/continuity and minimize signal interference.

Once you change something all bets are off and each truck behaves differently based on the circumstances. It could be a bulb change/conversion, it could be where you park (near antennas, signal lines, etc.), or it could be you (the Owner's Manual mentions that you might get fob interference if your cell phone is close to it).

I have not had interference issues with Lasfit (neither before or after changing the settings in the BCM) but others have. Same can be said for Diode Dynamics or the laundry list of budget options on Amazon.

My last truck was a 2003 Ford that had halogen headlights and was light on shielding as none of this stuff was around when it was designed. I read of many people having interference issues when adding modifications to modernize the truck (HID headlights, wireless options, etc.) to the point where some functions didn't work including the truck would shut down as it interfered with the ECM signals (which required more modification to prevent that).

Unless you know where the issue is you don't have much choice besides live with it, keep changing bulbs until you find ones that work, try changing the brake light back to stock halogen (I hear that solves the issue for some), or change them all back to stock. I've also read a thread where someone shelled out some serious cash for the OEM LED CHSML and that worked.
 
I had the original LasFit and had interference, no key fob found. Then I tried the newer version that everyone is talking about, and the same thing. So I went back to the factory bulbs and no problems. So things just aren't worth the effort and frustration.
 
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Interference. Whether it's radio frequencies or some other invisible magic beams it's having a hard time sensing the fob (I think the hub is in the roof near the CHSML).

With all the technology these days, especially wireless, the air would be thick with it if you could see everything that's going on.

The truck is designed a certain way. Wire bundles, antennas, and shielding are installed to maximize signal connectivity/continuity and minimize signal interference.

Once you change something all bets are off and each truck behaves differently based on the circumstances. It could be a bulb change/conversion, it could be where you park (near antennas, signal lines, etc.), or it could be you (the Owner's Manual mentions that you might get fob interference if your cell phone is close to it).

I have not had interference issues with Lasfit (neither before or after changing the settings in the BCM) but others have. Same can be said for Diode Dynamics or the laundry list of budget options on Amazon.

My last truck was a 2003 Ford that had halogen headlights and was light on shielding as none of this stuff was around when it was designed. I read of many people having interference issues when adding modifications to modernize the truck (HID headlights, wireless options, etc.) to the point where some functions didn't work including the truck would shut down as it interfered with the ECM signals (which required more modification to prevent that).

Unless you know where the issue is you don't have much choice besides live with it, keep changing bulbs until you find ones that work, try changing the brake light back to stock halogen (I hear that solves the issue for some), or change them all back to stock. I've also read a thread where someone shelled out some serious cash for the OEM LED CHSML and that worked.
My understanding is the 2021 rams have halogen as the 3rd brake light. I have not looked to see if that is the case.
 
One of the very first things I did when I got the truck in Dec 2019 is stop by Oreilly's and pick up a few packs of LED for the CHMSL and used Sylvania 921 LED's and have never had any issues since. And from my Alfa OBD backup file, this is how it is right now: LED CHMSL Lamp Present: No
 

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