LED fogs not working

[WXman]

Ok, so my truck came with halogen lights.

I installed LED bulbs, flashed the truck using my Tazer DT programmer to activate "LED fogs ON". Everything worked flawlessly.

This has worked perfectly for nearly a full year.

Recently I "unmarried" my Tazer because I was taking the truck to the dealership for a software update. The tech did all available updates, and noted that he was finding a code for my lights not working. He asked me if I had changed bulbs. I told him I had and that I bet that's why they aren't working (because at that very moment the truck was programmed for halogens, not LEDs).

When I got back home, I reinstalled my Tazer DT and reactivated my LED fogs. "LED fogs ON". I have verified twice that this setting is intact. BUT....my fogs do not work now. The symbol in the dash cluster comes on as if the fogs are on, but the bulbs are not actually lit.

WTH is going on?

 

[securityguy]

Do you have a 12V power supply you can check the bulbs on to see they'll fire up outside of the truck? Or, you can take a volt meter to the fog light socket and see if you are getting 12+VDC at the socket.

 

[WXman]

Before I reinstalled the Tazer they'd blink, or maybe work intermittently. Since the Tazer reinstall nothing. The initial Tazer install was making them flawless. It's all very weird. But this weekend I guess I'll look into it in more detail. I wonder if the most recent 18-008-20 factory tune did something to render the Tazer ineffective? Hmmm.....

 

[securityguy]

Before I reinstalled the Tazer they'd blink, or maybe work intermittently. Since the Tazer reinstall nothing. The initial Tazer install was making them flawless. It's all very weird. But this weekend I guess I'll look into it in more detail. I wonder if the most recent 18-008-20 factory tune did something to render the Tazer ineffective? Hmmm.....

A factory tune should have no impact on this issue

 

[WXman]

So I unmarried the Tazer and the passenger side fog light came back on but the driver side is still off. Clearly it's a programming issue and I guess the easiest thing to do at this point is swap those back to halogen bulbs.

 

[RAM Patriot]

Since they operate at a different Voltage could the switch back to halogen have blown the LED circuitry?

 

[securityguy]

Since they operate at a different Voltage could the switch back to halogen have blown the LED circuitry?

Shouldn't have been an issue at all, but a good thought.

 

[WXman]

I just popped my factory halogen bulbs back in and both work normally. For some reason the latest software update caused the truck to really dislike having LED bulbs in the fog light position, even with the Tazer programmer set to "LED Fogs ON". Who knows.....

 

[mikeru82]

Since they operate at a different Voltage could the switch back to halogen have blown the LED circuitry?

What voltage do the LED's operate at? This could definitely have damaged the LED bulbs if the difference is high enough.

 

[securityguy]

What voltage do the LED's operate at? This could definitely have damaged the LED bulbs if the difference is high enough.

The same voltage as the halogens...non-issue.

 

[Fantastipotamus]

Hmm.. interesting. You swapped halogen fogs to LED fogs (just the bulbs?) and you had to use the Tazer? Did the fog manufacturer say that was necessary? I would think the ‘LED Fogs: On’ setting would be for using the OEM LED fogs.

I had halogens and installed LASFIT switchbacks LED bulbs and they worked without any sort of programming. Just swap the bulbs like I was going halogen->halogen. I do have a set of Diode Dynamics LEDs i got though, because the switchbacks were bothering me, guess I’ll see if they work okay, because I don’t own a Tazer.

 

[securityguy]

To install LEDs, you should not have to change the setting in the TAZER at all.

 

[WXman]

Correct, the truck comes from the factory programmed for halogen bulbs. LED bulbs will therefore blink, or cycle on/off, or sometimes not work at all due to the difference in pulse modulation. This is well known especially with Ram and Jeep vehicles.

Typically people will use a programmer to activate LED bulbs themselves, or pay the dealer $100 to do it. Then the truck will send the correct pulse to the bulb sockets to properly power the LED diodes.

On my truck, the Tazer programming worked perfectly for nearly a year. But after the most recent factory tune was installed, when I went to reactivate the LED bulbs with my Tazer it no longer is working. Which leads me to believe that something has changed in the factory tune that interferes with the Tazer command now.

 

[Fantastipotamus]

Correct, the truck comes from the factory programmed for halogen bulbs. LED bulbs will therefore blink, or cycle on/off, or sometimes not work at all due to the difference in pulse modulation. This is well known especially with Ram and Jeep vehicles.

My LASFIT’s, and many others, are plug and play. So it’s not a 100% certainty for all LED’s..

That doesn’t help with your issue though, best of luck. Personally, I would probably get frustrated and just buy another pair, and return them if they didn’t work, but that’s me, I hate troubleshooting electrical sh*t.