DIY LED brake lights. Need help.

[Izso]

suddenly all the sifus show up!

Stupidcar : ask the question and you'll peak their interest, post some pictures and stuff and you'll get their replies! (the sifus)

 

[stupidcar]

suddenly all the sifus show up!

Stupidcar : ask the question and you'll peak their interest, post some pictures and stuff and you'll get their replies! (the sifus)

Ya wor, anyways, just left a few leds to solder then the case only.

 

[TitanRev]

Stupid car, correct me if I'm wrong. I'm seeing 2 x positive cable and 2 x negative cable to power you arrays. You using battery to power the test or 12V DC? The LED you use are those normal ones? advisable to use a driver.

 

[stupidcar]

Stupid car, correct me if I'm wrong. I'm seeing 2 x positive cable and 2 x negative cable to power you arrays. You using battery to power the test or 12V DC? The LED you use are those normal ones? advisable to use a driver.

I think my colours of wires are wrong. But anyways, I know which is which lah.
I tested it using 9V battery, I'm gonna use it for 12V.

My LEDs specs are flat bed, 2.8v min forward voltage, 5000mcd, 20mA, 120-140 degree viewing angle.

Er, Okay, what I plan to do is.

The first 2 rows of leds are to be light up when I switch on taillights.
The last 2 rows only light up when I brake.

If I were to follow the functions of taillights and brake lights, I have to use driver lah.

 

[TitanRev]

I think my colours of wires are wrong. But anyways, I know which is which lah.
I tested it using 9V battery, I'm gonna use it for 12V.

My LEDs specs are flat bed, 2.8v min forward voltage, 5000mcd, 20mA, 120-140 degree viewing angle.

Er, Okay, what I plan to do is.

The first 2 rows of leds are to be light up when I switch on taillights.
The last 2 rows only light up when I brake.

If I were to follow the functions of taillights and brake lights, I have to use driver lah.

Aren't you building your 4th tail light with brake light function?:hmmmm: so surely need driver.

 

[stupidcar]

Aren't you building your 4th tail light with brake light function?:hmmmm: so surely need driver.

There are a total of 4 rows. First 2 rows I tap taillights function only. No brake light function.
The next 2 rows are for brake lights, no taillights function.

Taillights: Switched on with headlights
Brake lights: Lights up when you brake.

Tailights + brake light, i'm not doing that.

I think it will work because logically it will. I will just solder it then do a test run tonight.
It's just light your 3rd brake like assembly, just tapping different power points.

 

[TitanRev]

Stupidcar, just a suggestion for your DIY. Put the resistor before the diode. This helps regulate the voltage going into the resistor and the LED. Previously I didn't think of putting diode and use resistor as a form of voltage regulating but it was not very good as the voltage in car will vary from 12V to 14.5V. Also resistor's resistance sometimes might not be like what they stated. It's more safe to put a diode.

 

[vr2turbo]

There are a total of 4 rows. First 2 rows I tap taillights function only. No brake light function.
The next 2 rows are for brake lights, no taillights function.

Taillights: Switched on with headlights
Brake lights: Lights up when you brake.

Tailights + brake light, i'm not doing that.

I think it will work because logically it will. I will just solder it then do a test run tonight.
It's just light your 3rd brake like assembly, just tapping different power points.

The LED's all same wattage, how do you light them dimmer for lights and brighter for brakes. Only using the resistors?

 

[TitanRev]

The LED's all same wattage, how do you light them dimmer for lights and brighter for brakes. Only using the resistors?

VR2, no he's not making them dimmer. All the LED will be having the same brightness he only configure which row to light up on power and which to light up on when brake apply.

Example you have 4 rows of LED

4 rows you tap the power from the tail lights but 2 will tap from the source when you turn on lights the tail lights will be on. Another 2 tap from the source where there's only power when you apply the brakes.

IF use driver then only can achieve the dimmer and brighter effect as driver got 2 output.

 

[stupidcar]

Stupidcar, just a suggestion for your DIY. Put a zener diode before the resistor. This helps regulate the voltage going into the resistor and the LED. Previously I didn't think of putting diode and use resistor as a form of voltage regulating but it was not very good as the voltage in car will vary from 12V to 14.5V. Also resistor's resistance sometimes might not be like what they stated. It's more safe to put a diode.

Nvm lah, cheap mod.
From LEDs resistor calculator,
i put 2.8v forward current which is the minimum, maximum can go 3.2. Reverse is 5V.
I didn't use just one resistor for the whole setup, hopefully it will be okay.

Normal lights i put 5 LEDs for a 100ohm.
For brake light 4 LEDs, I put 100ohm because it doesn't stay on for so long so it can tahan.
I get it lah to maintain it's reliability. Thank you
But then my friend did it using this set up for dome light, it's been a few months.

The LED's all same wattage, how do you light them dimmer for lights and brighter for brakes. Only using the resistors?

Different set for brakes different set for tails function ma.
No need dimmer function, I tested it with multimeter from the brake lights plug.

---------- Post added at 04:48 PM ---------- 6 hour anti-bump limit - Previous post was at 04:47 PM ----------

VR2, no he's not making them dimmer. All the LED will be having the same brightness he only configure which row to light up on power and which to light up on when brake apply.

Example you have 4 rows of LED

4 rows you tap the power from the tail lights but 2 will tap from the source when you turn on lights the tail lights will be on. Another 2 tap from the source where there's only power when you apply the brakes.

IF use driver then only can achieve the dimmer and brighter effect as driver got 2 output.

Yeah, I get it. But i'm just experimenting.
I will only do this IF my taillights kaput.
This is just decorative.

 

[vr2turbo]

VR2, no he's not making them dimmer. All the LED will be having the same brightness he only configure which row to light up on power and which to light up on when brake apply.

Example you have 4 rows of LED

4 rows you tap the power from the tail lights but 2 will tap from the source when you turn on lights the tail lights will be on. Another 2 tap from the source where there's only power when you apply the brakes.

IF use driver then only can achieve the dimmer and brighter effect as driver got 2 output.

Different set for brakes different set for tails function ma.
No need dimmer function, I tested it with multimeter from the brake lights plug.

Bro. TR, Thanks for your info.

Why I ask is, if the LED light is bright as night lighting light, very annoying for rear car. Normal bulb uses 5w/21w filaments for this....night/brakes lights...

 

[stupidcar]

Bro. TR, Thanks for your info.

Why I ask is, if the LED light is bright as night lighting light, very annoying for rear car. Normal bulb uses 5w/21w filaments for this....night/brakes lights...

It is under, won't be shone directly and also I'm gonna dip the cover.

 

[vr2turbo]

It is under, won't be shone directly and also I'm gonna dip the cover.

So night light shine down, brake light shine out......

 

[stupidcar]

So night light shine down, brake light shine out......

Hahahahaha. Gonna dip my reflector too. Its kinda fugly to me.

 

[stupidcar]

Just need to fabricate the case then i'm done!
Badly soldered piece of crap. Hahhaah