Sequential LED strip not working when car is turned on.

Hey, thanks for the reply.
I tested the led strip again by removing the power wire from where it was connected and hooked it up straight to the battery.
The led strip started working with engine on and off.
I ordered a 36W DC-DC voltage regulator for it.
The input of the regulator is 8v-40v and output is 12v 3amp max.
The led strip specs say 12v and 10watts.
Using a watt converter calculator, 10watts translates to 0.9 amps.

Do you think this voltage regulator will work?
Thanks again.

Should. That range sounds like max/min car voltage anyway, from low-battery to alternator load-dump.

Still no idea why the strip should crap out at 14V. Unless they’re “generic” as in “use with a[ny] regulated 12V supply” and not made for a car’s “12V”.

Ok, great.
I am not sure why they didn’t work with the car on.
A few years ago I ordered some sequential side marker turn signal lights too. They replaced my the side marker on my fender and had a similar issue.
With the car off, the sequential light worked, but with the car on, the marker would flicker when I would use the turn signals.

Here is the led strip I ordered and the regulator.

Exterior Car LED Lights - Multicolor 2 Pcs 24 inches Daytime Running Lights, RGB Flexible LED Strip Light Kits - for Car Replacement Switchback Headlight Decorative Lamp and Turn Signal Lights\_encoding=UTF8&psc=1

HOMELYLIFE DC Voltage Reducer DC 36V 24V 12V to 12V 3A Buck Converter Voltage Regulator\_encoding=UTF8&psc=1


Sounds like you already got it figured out. Noticed on your amazon product page that it specifically says something about this: “(Pay attention: the working voltage is DC 12V, higher voltage may cause a short circuit problem, please check the voltage before installing)”

Cars vary a little, as do the sub-circuits, but generally you’re running at 14.4V with the engine on. So definitely need a regulator to make these dudes happy with a steady 12V supply.

Dad note: If your state has laws mirroring federal rules about accessory and/or off-color lighting and if your local folks enforce them, look out. Around here they go in spurts of cracking down on it. Usually it’s just for those who drive around with them on, but by statute, “key on” is the same as driving on public roads even if it’s in a privately-owned parking lot (retail, etc). Some places will flag a state inspection if they see them installed, too, so I hear (they don’t do that where I live, though).

I hope the regulator fixes it.
The sequential turn signal gives the car a nice modern touch.
I read the description and I completely missed that info they said.

I just want the sequential signal. The daytime running light, I am still on the fence about it.
Not interested in any colors flashing or anything.
How can I add images to show them?

Posting images help

Here are some images.
First image is the turn signal.
Second image is the daytime running light.

The daytime running light can change colors. But I will probably leave it set on blue or red to match the halo rings.

Wow, red on the front would get you a large ticket here. Could even fall into impersonation of a police vehicle. If you went blue and red, I would say your odds of an expensive interaction would go way up.

I do like it though.

Thank you.
I have had the red rings for years now and haven’t had any issues.
I agree with you, the red combined with the blue strip will probably draw more attention.
I will need to change the color of the rings or change the color of the led strip.

Not sure what colors cops in CA use, here in IL they are red and blue and do not like it when folks put that combo on the front or rear of a car. Might be more acceptable in the metro areas, but not sure. I do really like the concept.

I think the entire U.S. uses red and blue lights.

That's the way it is in California anyways.

I got amber lights on my rear deck but I don’t even have them plugged in or connected. The Y-adapter and power cable I keep separate and in the console, so there’s no question that I don’t use them “on road”.

FD is always red, and PD usually is blue and optionally red.

Eg, Chicago PD uses blue or blue/white. (I learned that just watching the show.)

Some townies (sheriffs, marshal, etc.) use only red, but I can’t think of examples offhand.

At night, some cops have a steady red (sometimes blue) light on top, called “cruise lights”. Good in case you get stuck and can see a cop’s coming vs some serial-killer.

I’m in California. Used to be a smallish town but it’s getting over populated, quick.
I have seen a handful of police stare at my headlights in the 4 years I’ve had them, but never gotten stopped.
I did want to set the led strip daytime light to blue/white. I see a lot of new cars like that, but I don’t want to get stopped. I’ll probably set the daytime light to amber.

Illinois is mostly red and blue, but Indiana is mostly blue. FD in Illinois is also red and blue with volunteers only allowed to run blue headed to station or scene, no red. Meat wagons are more often red, blue and amber. I always thought that these should be a standard.

This post may be long. PLEASE bear with me.

Well, I got the regulator today and it still isn’t working properly.
The regulator is huge compared to the black control box on the LED strip. About 5x bigger, the wires on the regulator are also about twice as thick.
Here is a link to the regulator I got. The box on it does say “for golf cart use”…?

HOMELYLIFE DC Voltage Reducer DC 36V 24V 12V to 12V 3A Buck Converter Voltage Regulator\_encoding=UTF8&psc=1

Now, with the car on, the LED daytime light seems to work fine. The colors change with the remote included in the kit. A few times the strip did revert back to a preset setting.(a very faint white light with no functions)

When I use the turn signal, the led strip will light up like it’s supposed to about 3-4 times. It then turns off, the daytime light turns on and turn signal works another 3-4 times and this just repeats itself.

This is how I have everything wired.

GROUND from LED strip box -> wired to ground on headlight harness
POWER from LED strip box -> wired to output wire from voltage regulator.
SIGNAL wire from LED box -> wired to turn signal on the fender of the car.

INPUT wire -> wired to power wire from headlight harness
OUTPUT wire -> wired to power wire on LED box.
GROUND wire (2 ground wires) -> I tied these 2 wires together to only run one wire to the vehicle chassis.

I tried pulling power from the battery, like before when it worked, and same issue persisted.
I have the input power wire on the headlight harness because the red rings and foglights light up when I unlock the car, I want the LED strip to also light up.
I can try checking voltage at the foglights/red rings with the car on to see if they are at 12v.

Otherwise, I am lost.

Is the regulator too big or too small? Is my wiring incorrect?

Here is a video of the LED strip with the car on and regulator installed and a video with the car off without regulator.

Any help is greatly appreciated.

This led box has a mind of its own.

I removed the led regulator box and removed the led ground wire from the headlight harness.
I attached the ground wire to chassis ground and now it decides to work. I then attached the ground back to the headlight harness it decides to work.

I decided to pull power from the foglights and the strip worked. I thought I figured it out, for the 6th time. After a while, the strip reverted to the pre set low light setting.
I even adjusted the voltage on the lighting module so the foglights only revived 12v.

I measured power at the +terminal in the engine bay where the led works great, it reads 14.5v with the car on!

Right now I have the led power wire on the headlight harness, ground on chassis and signal from side marker on the fender.
Seems to work ok. Once in a while the strip has a very quick stutter where it flashes quickly and then flashes normal. It’s also not in sync with the stock turn signal on the headlight.
They sync up once in a while but get get out of sync.

Can this out of sync be fixed with something?

At this point, would you guys blame the cheap/defective led strip? Or the wiring?

Is your turn and/or all the lighting circuit controlled by relays or by the ECM? If the latter, that might be the issue…and if so, not sure if that could possibly be remedied. If the former, there might be a relay available that better provides what’s needed? I haven’t fooled with any turn circuits in many years…actually have hardly even had to change bulbs in a long time (awesome). I think I would just ground all the new wires to chassis and make sure it’s a good connection, just because…but clearly that isn’t the issue.

The wiring.

The power line in the headlight, side marker or fog light harness will be at a lower voltage (e.g. 12 V or lower depending upon the current load) than what is available at the fuse box. Run a wire from the headlight fuse directly to the Input of the voltage regulator and run the return back to the battery negative terminal.

Then run the Output of the VR to the input and return of the LED box. Any current out of the VR Output (+) must be returned back to the “ground” or return (-) on the VR Output side. Not to the chassis. Chassis is used to carry current back to the battery negative terminal which originated from the battery positive terminal. The VR Output is created by a transformer and is a separate power supply from the battery.

If the voltage to the VR input drops to 12V or less, then it no longer can sustain its Output. This will cause a power glitch or reset to occur in the LED box and cause the goofiness that you are seeing.

Thanks for the reply.

All the lighting and a few other things (locks/windows) are controlled by a footwell lighting module. I have a fuse box and relays but nothing is listed for lights, just the light module.

I wish I got into any car related circuits years ago. I see videos of people creating nice lighting set ups, especially sequential led strips in the tail lights and I envy them.
I work on this light project for about an hour a day. Either when I think of something else to try or have directions from you all here on what to do.
Currently I just have the wires twisted together. I hard wired everything like 3x only to find out it was incorrect. I will hardwire everything once it’s 100%.