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Fri Aug 24, 2012 9:54 am

I have been told my tail lights are flickering while driving the buggy.

I have these tail/stop/turn led lights,

http://www.etrailer.com/p-STL42RB.html

From some searching I have found people run capacitors to fix this problem to give the lights steady voltage.

Has anyone run into this problem? Do I just need to wire some capacitors in line? If so what size should I get?

Thanks for any help!

Fri Aug 24, 2012 9:59 am

Just what are you describing as a flicker??? Flashing off and on at random intervals or a steady cyclic flicker like a timed circuit...

IF you tail lights are flickering randomly, to me it indicates a bad connection someplace in your wiring..... I have yet to see any properly wired LEDS flicker in tail lamp circuits.... Need more information....

Dale

Fri Aug 24, 2012 10:07 am

Well the problem is I haven't seen my self so Im not 100% sure, I will have to do some investgating to try to replicate it while I'm looking at it.

Will report back with more info.

Fri Aug 24, 2012 10:11 am

I have the technostalgia LED lamps on the rear of my buggy. They appear to ‘flicker’ when observed
out of the corner of my eye. When I look straight at them, I do not notice the ‘flicker’. I have learned
to realize that people who notice the ‘flicker’ are actually paying attention to the lights.

Here is how the manufacturer describes the lighting process for the tail light function:

"Pulse width modulated tail lamp. The reduced intensity taillight now is a rapid pulsing of the LEDs on and off (on for 10%
and off for 90% of the time). This pulsing repeats 2000 times per second. Since the LEDs are only on for 10% of the time, their life
is increased. The DOT defined minimum brightness ratio of 7:1 between to tail and stop light is exceeded to 10:1."

Some LED turn-stop/tail lights which use the same LED elements, actually switch the power on for only 10%
of the time. This happens so quickly that the observer will think that they see a dimmer light. Unfortunately
this will cause a lot of people to see a ‘flicker’ in the lamp.

Fri Aug 24, 2012 11:32 am

Hmmm....... IF this is so.... Putting a capacitor across circuit is not going to do anything to decrease flicker because the flicker is initiated within the LED assembly it self...

Dale

Fri Aug 24, 2012 11:47 am

nightmanx11 wrote: I have the technostalgia LED lamps on the rear of my buggy. They appear to ‘flicker’ when observed
out of the corner of my eye. When I look straight at them, I do not notice the ‘flicker’. I have learned
to realize that people who notice the ‘flicker’ are actually paying attention to the lights.

Here is how the manufacturer describes the lighting process for the tail light function:

"Pulse width modulated tail lamp. The reduced intensity taillight now is a rapid pulsing of the LEDs on and off (on for 10%
and off for 90% of the time). This pulsing repeats 2000 times per second. Since the LEDs are only on for 10% of the time, their life
is increased. The DOT defined minimum brightness ratio of 7:1 between to tail and stop light is exceeded to 10:1."

Some LED turn-stop/tail lights which use the same LED elements, actually switch the power on for only 10%
of the time. This happens so quickly that the observer will think that they see a dimmer light. Unfortunately
this will cause a lot of people to see a ‘flicker’ in the lamp.

This. I've noticed a flicker on the newer cars like Cadillac and Lexus with the LED tail lights, but only if I'm not looking at them directly. Try it yourself on your buggy - park it outside one night and put the lights on. Only then will you be able to tell if it's that phenomena or something else mechanical. Have someone bounce the car while you're looking at it to make sure it's not an electrical connection.

Fri Aug 24, 2012 11:26 pm

nightmanx11 wrote: I have the technostalgia LED lamps on the rear of my buggy. They appear to ‘flicker’ when observed
out of the corner of my eye. When I look straight at them, I do not notice the ‘flicker’. I have learned
to realize that people who notice the ‘flicker’ are actually paying attention to the lights.

Here is how the manufacturer describes the lighting process for the tail light function:

"Pulse width modulated tail lamp. The reduced intensity taillight now is a rapid pulsing of the LEDs on and off (on for 10%
and off for 90% of the time). This pulsing repeats 2000 times per second. Since the LEDs are only on for 10% of the time, their life
is increased. The DOT defined minimum brightness ratio of 7:1 between to tail and stop light is exceeded to 10:1."

Some LED turn-stop/tail lights which use the same LED elements, actually switch the power on for only 10%
of the time. This happens so quickly that the observer will think that they see a dimmer light. Unfortunately
this will cause a lot of people to see a ‘flicker’ in the lamp.

My taillights,brake lights and blinkers do not require the key to be on for them to work, so if I understand this correctly this (pulse) is something that will be happening when the LED lights have power going to them even though the lights aren't necessarily on?

Wed May 21, 2014 4:58 am

I know this is an old post but since the subject is appropriate, I thought wise to continue on this thread.

I too have a flickering problem with my tail lights. I'm running Technostalgia LED retro kit on our Kick-Out-S.S. and when the lights are on, from time to time one of the lights will randomly flicker. I'm not refering to the pulsing effect here.

The lights are equiped with circuitry that make them pulse when you 1st press on the brakes. The random flickering is close to that effect but only 1 light at a time and very random. I have not monitored if engine RPM is related but I have witnessed it at idle, other times it was reported by people following me.

I have not witnessed it flicker with the engine off which leads me to believe it's mag interference. Could the tachometer wire from the coil to the tach be causing some sort of interference?

Someone mentionned adding a capacitor across the circuit. Would this resolve interference problems? If so, what type of capacitor am I looking for and how does one go about adding it?

The wires that came with the unit are really small gauge. All the wire connections are all properly solderer with union sleves and shrink wraps. All the grounds are all terminated on a ground block.

There is a CB antenna near the light but this was recently added and the problem existed before adding the antenna/CB. When I TX on the CB, the right light does get affected which leads me to bielive that these units are prone to RF or ignition system inteference.

Thanks for your help.

This is the light I'm refering to:

This it the back of the buggy:

Wed May 21, 2014 5:31 am

Are you guys running generators or alternators? If you look at a home light bulb on 60 hz. you would not see the flicker. At 50 hz. you can see the flicker, barely. LED are electronic and turn on and off, instantly. Bulbs have filaments that are slow reacting, in comparison. If the circuitry is a "switching" type to save LED life, it may be a little too short "on" time and too long "off" time. You could see it clearly with an oscilloscope.

Wed May 21, 2014 5:38 am

Roys_Big_Toys wrote: Are you guys running generators or alternators? If you look at a home light bulb on 60 hz. you would not see the flicker. At 50 hz. you can see the flicker, barely. LED are electronic and turn on and off, instantly. Bulbs have filaments that are slow reacting, in comparison. If the circuitry is a "switching" type to save LED life, it may be a little too short "on" time and too long "off" time. You could see it clearly with an oscilloscope.

We're running a 75amp Alt. I undrstand what you're saying Roy but in this case it's not a pulsing problem, I can see the 50hz on/off effect when not looking straight at the light, that's ok. The problem is I get 'real' intermitent flickering of the brake/flasher light when the regular tail lights are on. It has the effect of me rapid turn signalling. This will be anoying for the people following us on ECVW.

Wed May 21, 2014 8:17 am

Vincent,

We have talked about this before, and there is a definite open condition tat occurred when you have the tail lights
on and are running down the road. It is not the flicker that all technostalgia tail lights have.

There is a definite loss of either the ground side of the circuit or the 12V power to the individual LED array. It
appears to be random as to the interval between failures, and to the length of time that the circuit is dead.

The photo you posted shows what you are experiencing.

Have you tried to use an different or alternate ground back by the engine?
Are the ground connections almost sterile? some times these modern LED circuits are very fussy about their
grounds. They do not like paint, dirt, oil, rust, etc. on the connection.

On my EMPI Sportster, I had a similar problem and ended up grounding the LED arrays at the lamp assembly.
There was something about the wiring and termination at the front that the LED did not like. I have not had
the problem since then. The Sportster is a metal body.

You are correct in that it causes the driver behind you to go nuts. But then they also back off a bit and allow
extra room to see what you are going to do next.

Wed May 21, 2014 9:41 am

^^^^ What is said above....

Any random flicker is probably from poor power wiring or grounding....

When grounding a lamp fixture you need to use at least same wire size as power wire to fixture and ground side is other half of circuit.... Actually the larger gauge ground wire the better....

The standard pulsed lighting from turn signal or brake application should not be interpreted as random flicker....

When describing the problem one has to be sure the description accurately identifies what one is trying to describe...

I have always found LED lighting to be very stable and never to have random flickering.... But do love Technostalgia's pulsed design for brake applications, sure gets peoples attention when they are following you....

Dale

Wed May 21, 2014 11:23 am

Dale M. wrote: ^^^^ What is said above....

Any random flicker is probably from poor power wiring or grounding....

When grounding a lamp fixture you need to use at least same wire size as power wire to fixture and ground side is other half of circuit.... Actually the larger gauge ground wire the better....

The standard pulsed lighting from turn signal or brake application should not be interpreted as random flicker....

When describing the problem one has to be sure the description accurately identifies what one is trying to describe...

I have always found LED lighting to be very stable and never to have random flickering.... But do love Technostalgia's pulsed design for brake applications, sure gets peoples attention when they are following you....

Dale

Joe and Dale, I double checked the grounding and wirering and can assure you everything is perfect. The ground wire is perfectly grounded to the grounding terminal.

I understand about being accurate in describing the flicker problem and let me try to be as clear as possible:

When the regular rear lights are on (parking), one of the lights (either sides) will momentarely flash brighter (just like when you apply the turn signal) but with a much faster frequency. In fact the frequency closely matches the rapid fire of the initial brake light. I have witnessed it happen at idle with no one in the car touching anything (I saw it). My next step in describing the problem would be to video record the situation. I guess I could mount the GoPro on the back and go for a drive.

I contacted Cool-Leds, suppliers of these LED units and they agree that the source is most likely coming from electrical noise interference. They suggested I ship them the circuit boards and they would add a noise suppressors to the circuit and send them back. I'm inquiring about getting a new set with the noise suppressor added as I don't like the idea of not having rear lights... ;-)

Fri Jun 13, 2014 7:05 pm

I received the new circuit boards today. I'll try to install them tomorrow and see if that fixes the problem.

Left - Noise supressor unit
Right - Original unit

Notice the extra capacitors(?) at R11-R13-R14 and D15.

The manufacturer was pretty sure this fix would do the trick. I'll report back tomorrow.

Fri Jun 13, 2014 9:41 pm

I sure hope that this will fix the phantom disconnect problem.

Joe

Mon Jun 16, 2014 7:43 am

I finished replacing the circuit boards and the interference seems resolved but now I have an out of sync on the RapidFire after using the flashers.

I have to say that the company that produces these units are very supportive and responsive.

After contacting them, they confirmed that this is the behavior of the 'fixed' units.

Technostalgia wrote: Yes, the out-of-sequence RapidFire is due to the noise absorbing capacitors we had to add. After using the turn signal, the micro computer gets tricked by the capacitor for a few milli-seconds causing the out-of-sequence RapidFire.

There might be some electronics expert that could offer some advice on what component to add to fix the fix but at this point, I'm going to leave it alone for now.

I can confirm that the interference supressors are working as the CB antena was causing the module to flicker whenever I keyed the mic. This no longer happens.

Sun Jul 20, 2014 6:07 pm

vincent9993 wrote: I received the new circuit boards today. I'll try to install them tomorrow and see if that fixes the problem.

Left - Noise supressor unit
Right - Original unit

Notice the extra capacitors(?) at R11-R13-R14 and D15.

The manufacturer was pretty sure this fix would do the trick. I'll report back tomorrow.

Resistors are used with LED's... (12VDC applications)
Capacitors labeled on a circuit board would be a C..
Resistors use R.

(just passing thru reading posts and saw this one)

Sat Mar 21, 2015 1:37 am

If you don't mind me asking, where'd you get those lights/boards? I've been looking for something like that for my buggy, looks good!

Sat Mar 21, 2015 3:37 am

Thanks for sharing your experience with this problem.

I'm guessing you may have wire core plug wires and non-resistor spark plugs.

RMI suppressing plug wires such as helical wound may have prevented the first problem.

Sat Mar 21, 2015 7:07 am

eschmi wrote: If you don't mind me asking, where'd you get those lights/boards? I've been looking for something like that for my buggy, looks good!

Check... http://www.cool-leds.com/

DALE