LED Swap - Problems...

[98chevy2500SS]

Finally bought some LED parking lights, Halogen clear headlights (love the nice cut-off line at the top! So much better than stock housings!), and LED tail lights (so much brighter!). Super excited once they were in, and are a lot better over the ol' incandescent's. But I seem to be having a problem with LEDs in the side markers and when I turn on my lights, on the instrument cluster, both the green turn signal bulb indicators are lit, but dim, once I flick on my turn signals, they bright up. I don't get why that is happening.

With the side marker LEDs, I installed some Sylvania 194 Amber LEDs that I bought awhile ago. Problem is, when I turn on all of the lights and flick the turn signal switch, they work, but when I turn off the lights, then flick on the turn signals, nothing happens in that marker. I go to flip the bulb, they finally work, but then once again I turn on my headlights, nothing happens. I don't get it. Is this my tail light's and parking light's fault? Do I need to have those box resistors installed even though I have the EP29 flasher? This is all new to me, I am not understanding what is happening here, I really don't want to have to send these LED parking lights back and get the clear turn signal housings with incandescent bulbs in them. If someone could point me in the right direction, that would be great!

Thanks.

 

[someotherguy]

The resistors won't have any effect on whether or not the signals light up. The resistors are simply for correcting the flash rate. If you have the EP29 flasher you should already have that covered.

This is probably an incompatibility with the LED park lamps and the LED corner marker bulb. Try temporarily putting regular bulbs in your park lamp sockets, make sure they're oriented and working correctly, then see what results you get out of the corner LED bulb.

Richard

 

[98chevy2500SS]

Last year when I did the the led in stock tail light thing that miserably failed in June, I did try that while I had the parking lamps apart and they still didn't work. Kind of made me confused why they didn't work. I could try it again and see what happens, I will probably get back to you tomorrow in the afternoon sometime.

 

[someotherguy]

I'm talking about strictly the front park lamp sockets, not your taillights. For the taillights you would have needed to use SRCK-compatible LED's in the middle socket (the one that is both brake and turn signal function) for them to work properly.

Richard

 

[whiteboyslo]

You need side marker bulbs that aren't polarity-sensitive. You could put the original filament-style ones back in, but then the turn signal arrows on the dash will be fully lit when the parking lights are on, at least while using LEDs in the front turn signals.

I know all this because I JUST went through it all myself. I put switchback LEDs in the front turn signals and basic one-way LEDs in the corners, and had the issue where the corners only worked if headlights are on (or vice versa if you flipped the bulb). Then I put original-style bulbs back in the corners only to have the arrows on the dash on whenever the headlights are on. Finally put in the right kind of LEDs in the corners. Now they work fine, though I do get the faint glow in the arrows with this setup. I'm OK with that.

Link to bulbs: Alla Lighting 10pcs 2018 Newest Version Miniature T10 Wedge 2835-SMD High Power Super Bright 194 168 2825 175 W5W LED Bulb -- 6000K Xenon White LED Lights Bulbs https://www.amazon.com/dp/B076YPCSL5?ref=yo_pop_ma_swf

Mike

 

[98chevy2500SS]

Thanks Mike, yeah I think these Sylvania 194 LEDs I have are polarity sensitive most likely. That faint glow of the turn signal indicators on the cluster bothers me though, lol, but I would rather be fully LED than not.

I wonder why the turn signal indicators on the cluster have a faint glow, must just be the LEDs low power draw?

 

[df2x4]

Stuff like this is part of the reason I left all my exterior lighting incandescent. Sounds like an absolute nightmare and the glowing arrows would drive me insane.

 

[ima93chevyguy]

I have all led exterior lights, this happened to me once, all I did was I had accidentally plugged in one of the parking light plugs in the wrong way and it screwed everything up. I would check there first to make sure they're in the right way. They should go in more easily one way than the other.

I have the led parking lights and Sylvania 194 in the corners. Never had a problem other than this one time I plugged them in wrong.

 

[someotherguy]

Stuff like this is part of the reason I left all my exterior lighting incandescent. Sounds like an absolute nightmare and the glowing arrows would drive me insane.

It really depends on the exact combination of LED's. It can be a pain sometimes. Other times they just...work like they should!

When I had LED replacement bulbs in the park lamps and the stock taillight sockets on my 2006, I got a little bit of that "feedback" glow in my turn signals in the dash cluster and on the side mirrors. Later I swapped the tails out for full LED tails and the problem went away.

I did switchbacks on my '94 C2500LD with LED replacement bulbs in the stock taillight circuit boards (SRCK style in the middle socket as required) and the switchbacks didn't want to work right. I had already hacked the flasher to function similar to what an LED flasher does, so the flash rate wasn't an issue. The switchbacks are looking for a voltage change to "know" it's time to turn off the white running light function while the amber function is flashing. Mine were shutting off when they shouldn't. Adding load resistors back into the circuit fixed it, for whatever reason. I think in most cases switchbacks are in a single bulb scenario; the double bulb park lamps of a GMT400 are fairly unique when compared to many other vehicles, so having 2 on each circuit must have confused the switchbacks.

(I've been dealing with LED's on vehicles since...2000 or so! with varying degrees of success)

Richard

 

[98chevy2500SS]

@ima93chevyguy, thanks for your response, I will try that tomorrow.

@someotherguy, I have thought the switchbacks where neat, but never wanted to mess with them, didn't know it wasn't going too well for you. Once I got these new LED tail lights, they blew me away, definitely worth the $100, plus they look good.