LED in speedometer overheating - Toyota Nation Forum : Toyota Car and Truck Forums

Zain · 12-03-2011, 03:32 PM

hey guys i just swaped the bulbs in my speedometer with 5smleds and it was fine for like 10 mins but now its making the the bulb holder hot
and burning smell can be noticed

it was looking great but what cud be the problem?

is it because of 5 led bulb or any other reason?

***Zembonez*** · 12-03-2011, 04:15 PM

Sounds like you put a bulb in that requires more amperage than the tiny socket is designed for.

Zain · 12-03-2011, 07:06 PM

i thought LED uses less energy
would you reccomend any specific kind of led

like one of the bulb would start flickering after a while
and the holder gets really warm

xpeed · 12-03-2011, 10:05 PM

Which bulb did you swap out? The 194 or 74? Where did you buy them?

Zain · 12-04-2011, 05:50 PM

i swapped 195 bulbs

the leds i bought for 74 did not fit the holder
also i bought them from ebay

Monoxide MS · 12-04-2011, 07:42 PM

There's a good chance the LED's are being overdriven. Do the LED's themselves get warm or hot? If one of them is flickering, that can indicate too much current. It will likely fail and take out the remaining LED's.

What color are they? It can easily be fixed with a resistor.

xpeed · 12-04-2011, 09:35 PM

ebay LEDs are cheaply made. I'd rather buy them off from superbrightleds.com. They're of higher quality and should not have any problems with overheating issues. My guess is that the LED doesn't match up correctly with the voltage changes as well as a good quality LED bulb does. The solenoids are probably poorly done, that's why it's overheating. This is actually a first I've heard LEDs overheating. It should never happen since your fuses will take the load, not the other way around.

Color doesn't matter, nor do you need resistors in the gauge clusters since the 74 and 194 bulbs have similar voltage range as regular bulbs does, if not, should use less voltage. Buy them from superbrightleds.com and see if you still have any problems then.

Can you take a picture of the bulb and post it here so that we can help you out a bit more?

Monoxide MS · 12-04-2011, 09:57 PM

If the LED's are being overdriven and getting hot, a resistor will reduce the current and keep the LED's from overheating.
Manufactures of cheap plug and play bulbs tend to run them at a current higher than the LED's recommended rating to produce more light. Another possibility is that the manufacturer designed the bulb to work correctly with a 12V source, when in reality a running car can have anywhere from 13 to 14V or more. As a result, they get hot and die.

Knowing the color can help in determining which resistor is necessary since red, yellow and orange LED's usually have a 2 to 2.6 forward voltage drop. Blue, green and white are usually between 3 and 4V.

But I agree, the easiest solution is just buying a higher quality replacement bulb.

bolink654 · 12-05-2011, 01:35 AM

I did blue LED everything, in my 98.

I started by buying cheap china LED's from eBay, like you. And then a bunch of them did what you describe, then went out.

I emailed the people (and also checked the resistors they'd used.)... they are only designed for pretty much 12 volts. As Monoxide said, cars put out 13-14 volts when running.

Me personally, I bought a 100 pack of bare LED's and resistors, and used the bases from the china LEDs to make my own.

However, I am going to ask my own question here. I've built like 6 different bulbs for the 194 behind the fuel gauge, and that thing continually blinks, and eventually goes out. I've even built them so that they would be good for around 16 volts (of course at the cost of brightness) and it still does it. I've built LED strips for the footwells, I did the AUTO button in the window switch, the cig lighter ring - all the crap that they don't "make" a bulb for, and had NO problems. But that fuel gauge bulb has been giving me hell.

Raccoonnookkeeper · 12-15-2011, 02:04 AM

Hello. I read that there was a concern about voltage control for the LEDs being installed. Some of the posts mentioned using resistors to limit voltage. That can work, but it also has limitations that can be overcome by use of a voltage limiting device. There are low-cost voltage regulators available from electronics shops.
Some of the regulators have the output set by additional circuitry, but some of them are preset for a particular voltage you can specify when you purchase them. You may want to consider the use of a one of those voltage regulator circuits between the supply (output by the alternator and battery) and the bulbs you are installing.
One of the advantages of using a regulator is that the voltage it passes to the LED will be the same, regardless of the forward voltage drop mentioned by Monoxide MS. One of the consequences is that you can change the color of the LED without having to change the rest of the circuit, in case you decide change the color.

I hope this information is helpful.

Nark · 12-15-2011, 02:57 AM

Quote:

Originally Posted by Zain

hey guys i just swaped the bulbs in my speedometer with 5smleds and it was fine for like 10 mins but now its making the the bulb holder hot
and burning smell can be noticed

it was looking great but what cud be the problem?

is it because of 5 led bulb or any other reason?

Is this thing even design to be use inside the cluster? 5 led that's a lot.

OK, never mind just found it. Assuming that this is 3020 series then it only 1.2Watts. So it shouldn't be that hot compare to original bulb which is about 3 or so.

Nark · 12-15-2011, 03:20 AM

Quote:

Originally Posted by bolink654

I did blue LED everything, in my 98.

I started by buying cheap china LED's from eBay, like you. And then a bunch of them did what you describe, then went out.

I emailed the people (and also checked the resistors they'd used.)... they are only designed for pretty much 12 volts. As Monoxide said, cars put out 13-14 volts when running.

Me personally, I bought a 100 pack of bare LED's and resistors, and used the bases from the china LEDs to make my own.

However, I am going to ask my own question here. I've built like 6 different bulbs for the 194 behind the fuel gauge, and that thing continually blinks, and eventually goes out. I've even built them so that they would be good for around 16 volts (of course at the cost of brightness) and it still does it. I've built LED strips for the footwells, I did the AUTO button in the window switch, the cig lighter ring - all the crap that they don't "make" a bulb for, and had NO problems. But that fuel gauge bulb has been giving me hell.

Did you put 1 resistor per 1 LED in series? If you use more than 1 LED then you'll also need to put resistor in parallel as well. What I'd do is increase your dimmer to the max and then take the reading. Do the EI formula for series resistor and that will be the fix Voltage for LED. You should try Voltage variable LED. It can change color when you change the dimmer.

Hajoca · 12-15-2011, 10:33 AM

Does dimming the display reduce the burning smell??

Zain · 12-18-2011, 09:37 PM

yeah ive been using the dimmer and its all the way down and not making any smell

btw what leds i can use to get the most light without burning smell

i found a couple of them on superbright led.com
but not sure which ones to use

Hajoca · 12-19-2011, 11:50 AM

The dimming function reduces voltage to the lighting circuit.

|The LED assemblies (that is what I am calling your bulbs) need to have proper way to limit the current that the LED will take, too much and the LED heats up and burns out.