Poflex Technology Co., Ltd

How to evaluate safety of brake light?

Regardless of their appearance, LED bulbs emit light in a different way from filament bulbs. In contrast to a filament bulb, this means that just because an LED bulb physically fits in a lamp does not guarantee that it will function safely. It's critical to assess the performance of the specific lamps on your car because safety in this context entails much more than just lighting up in the appropriate color. The only reliable go/no-go test can be obtained in a test lab, but for the majority of people, this is not practical.

Install one of the LED bulbs and leave the standard bulb on the opposite side of the car so that you can make a reasonable visual assessment. While the car is outside in the bright daylight, turn on the lamps. Moving in an arc (180°) from one side of the car to the other while keeping both lamps in sight will allow you to gauge the visibility of each lamp from a distance of about 25 feet. Be aware of how bright the lamps appear, the apparent size of the lit area, any "dropout" angles where the lamp appears to go dark, any "flash" angles where the lamp appears extra bright, shadows, etc. After that, increase the distance between you and the car and walk both ways once more to compare the two sides.

When it is completely dark outside, park the car about 4 feet from a wall or garage door, facing 90 degrees (not crooked), turn on the lights, and measure the apparent brightness and size of the light patch produced by the two lamps (still using one standard bulb and one of the test LED bulbs). If you can find one, a handheld light meter is extremely helpful in this situation.

That LED bulb fails in that application if the light patch on the test bulb's side is smaller, dimmer, has dark streaks or shadows, or if there are viewing angles where the LED bulb is less visible than the filament bulb. Of course, if you do notice any shadows, bright spots, or other artifacts, make sure the standard bulb doesn't have a similar artifact on the opposite side. Always compare the apparent bright/dim ratio between day and night. Frequently, an LED retrofit will not have enough contrast between the bright (brake or turn) and dim (tail or park) modes, which is extremely dangerous and effectively renders the lights useless for communicating the messages they are intended to.

None of this is enough to conclusively determine whether the test bulb is adequate, but if the test bulb is sufficiently subpar, it is enough to reject it.

Important details.

LED red bulbs are necessary for lamps with red lenses. You won't get a safe amount of light if you place a white LED behind a red lens. This advice might change if reliable white LED bulbs with color temperatures at or below 3000K become available; if that happens, this post will be updated. However, as of this writing, all reliable white LED bulbs have color temperatures that are significantly higher than that and are therefore unsafe or ineffective for use with red lenses. This means that there are some applications where a reputable LED bulb fits and is optically compatible with the lamp (spreads the light appropriately), but the color incompatibility makes it a dead-end. For instance, there is no reliable red 921 (W16W), so center brake lights that require this type of bulb are out of luck. It is best to steer clear of a yellow/amber LED with a red lens.

You can use white or yellow/amber LEDs in lamps with yellow/amber lenses. An LED that is white and has an amber/yellow lens will produce light that is more yellow than amber. The majority of the time, this shade will fall within the permitted range for yellow/amber turn signals, and in rear turn signals, the greater color separation from the neighboring red brake-tail lights can help the turn signal be more noticeable.

If you decide to proceed, install the flasher (or configure the body computer) that is used for trailer towing, or install a resistor in each feed wire for the turn signal using sturdy connectors to achieve or restore the proper turn signal flash rate.