Has anyone replaced tail lamp bulbs with LED?

tirefriar

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Thanks. Not sure whats going with mine.... Will open up the lamps and see if the bulbs are "seated" all the way into the plug and contacts are lined up although they work properly in a 4 way operation...
 

08MustangDude

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So, they work with the 4-way (flashers) on, but not turn signals?

Do you have parking lights?
 

08MustangDude

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The "click" you hear with the signals and flashers is from a speaker, not
an actual relay, FYI... Put the key in, open the door for the warning. and
put your 4-ways on, you won't hear the clicking noise while the warning
is sounding.

The SJB controls the signals... In your case, if you want LEDs as signals,
you will need load resisters. You only need a value that will allow them
to work. Me, personally, if I have to use load resisters, I won't put an LED
in. I use them for the low power consumption, and the load resister will
defeat that purpose.

Also, as I asked above, with those tails you have? Did they come with a
different harness too? IF so, plug your factory harness back in, put
three LEDs in , and test the signals. IT could be with just the two, it's not
getting the load it needs to activate them... Do you get a hyperflash on
the dashboard indicators, or any other warning?
 

tirefriar

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I did not elect to replace the harness with an aftermarket sequential one from AmericanMuscle, so the harness is OE. Tail lamps function as they should in all modes except when the turn signal switch is turned on. Then I get hyper flashing at the front blinkers and no lighting whatsoever from the rear blinkers. The 4way flashing could be going through a different circuit that overrides low voltage (I am just guessing here)...

I just went out to the car, turned key to position#2. Turn signals work perfectly, both left and right. 4 way works too. I hear "clicking".

Which the left turn signal is on, I start the engine. Operation of the signal remains normal. I then switch to right turn signal and thats when hyprflashing occurs. Going back to the left signal still experience hyper flashing. "Clicking" noise is more rapid, in line with the blinking frequency.

Could this be affected by having one incandescent bulb left (the inner most as its blocked off by Saleen trim piece)?
 

08MustangDude

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No, I had one regular bulb in the outer lights on both sides for
a week or so, and that did not effect the turn signals at all.

I would try though, pull one LED from the other side, and place it in the
blocked side, and see what it does.. Sounds like your SJB just doesn't
like LEDs.
 

tirefriar

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Great idea with the bulb swap, will definitely try that. I’m going to hook up a decent scanner and go through the sequences described above to see if the error can be pin pointed. My reason for going LED was to get a brighter output to combat tinted lenses, hence I may end up installing diodes if that’s the cure. Incandescent bulbs are not bright enough to provide good visibility through the tint.
 

JEWC_Motorsports

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I only use bulbs from superbrightleds and i make sure they have resistors built in to them. I havent replaced any bulbs since swapping in 2013.
 

Juice

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The hyperflashing is an indication to the driver that one or more bulbs are out (incandescent). So when you put LEDs in, the sjb thinks there is a bulb out due to less draw from LEDs.

4ways do NOT hyperflash even with bulbs burned out
 

tirefriar

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I only use bulbs from superbrightleds and i make sure they have resistors built in to them. I havent replaced any bulbs since swapping in 2013.

i contacted superbirghtleds and the only 3157 canbus bulb they have is in amber, red is not available.
 

JEWC_Motorsports

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My mustang doesnt have canbus for the lights. If i have a light out i dont get a notification on the dash.
 
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08MustangDude

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The hyperflashing is an indication to the driver that one or more bulbs are out (incandescent). So when you put LEDs in, the sjb thinks there is a bulb out due to less draw from LEDs.

4ways do NOT hyperflash even with bulbs burned out
We covered that, and the SJB controls the turn signals.

My mustang doesnt have canbus for the lights. If i have a light out i dont get a notification on the dash.
The indication is either hyper-flash, or dash indicator. My VW has both...
My Mustang, don't know, I get no hyper-flash with the LEDs, no load
resisters (not diodes, tirefriar). Like I said, if I have to use them, then I
don't use LEDs.
 

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