To click on"Osram Sylvania Lamp Replacement Guide " to find out the sockt you need.(you will be redirect to Sylvania's website)

2.P21W/5W led socket reference

For 3157 or 7443, in case the Dim mode and Bright mode are reversed, how to correct this without reversing the stock harness

5.Solutions for common problems
Why does this happen & what is needed to install resistors?
LED bulbs have less resistance than conventional filament bulbs. If you are experiencing any of the above issues using LED bulbs your car will have a system in place to detect less load. The solution is a ballast / load resistor kit of the correct value to mimic the resistance of a normal bulb.
This kit will enable one LED bulb (of any type) which was previously rated at 5W or less to work normally. Examples include : W5W/501, R5W, BA9S etc.
After fitting LED light bulbs to some cars, you may experience one of the following issues :
Indicator bulbs flash faster than normal
Dashboard warning systems indicate that a fuse has blown
Dashboard warning systems indicate that a bulb has blown
Bulbs simply do not work when fitted to the car (yet, when tested directly from a 12v DC source the bulbs function normally.)
What type resistor should I install at when?
50W/6 OHM  P21W,P21/5W/ T20/S25 25W conventional bulbs, like ba15s,bau15s,bay15d/
25W/25 OHM  W5W,C5W,H6W 5W Conventional bulbs. Like T10,ba9s,festoon.
10W/39 OHM  For dashboard installtion

                     check to download the file


Which Color LEDs should I use?

For best results the LED color should be the same as the lens color or if bulb is behind a clear lens, use the appropriate color for turn and brake light functions. As an example: a red lens will filter out all but the red portion of the light so if the light is all red, none or very little light will be blocked by the lens. The light from a White LED contains very little light in the red portion of the visible spectrum so most of the light would be filtered out by a red lens.
Lens color diagram

                                                             This Picture comes from Superbrightled

Turn signal issues with LED bulbs

LED brake/tail lamps will not flash with thermal flasher units due to their extremely low current draw. Also, with stock flasher units, the turn signals may flash faster than normal (Hyper-Flash) or trigger bulb-out indicator on dash. Some vehicles will also disable the cruise control system if a brake light bulb is being indicated as bad. These installations will require an electronic flasher unit, available in our car bulb shopping category (for some vehicles) or at your auto parts store. Flashers designed to work with LED bulbs will often say "LED compatible". HEAVY DUTY flashers may also work with LED bulbs.

We offer some LED Flashers but we do not know which one (if any) will fit your vehicle. You will have to compare the pin-out of your flasher with the pin-outs of the flashers we offer, to see if we have a match, BEFORE you order one. Sorry but we do not have a flasher application list or the expertise to tell you which of our flashers will fit your vehicle.

Another fix is the installation of Load Resistors which are wired across (in parallel with) the turn signal bulbs to simulate the load of a standard filament bulb. We also have these available in our car bulb shopping category

Brightness of LED Car Bulbs

Standard LED bulbs are generally not as bright as standard incandescent bulbs, they have many advantages over filament bulbs (longer life, faster on/off times, lower power consumption, more vivid colors) but brightness is not one of them. They are generally not as bright but some of them with large numbers of LEDs, will appear brighter than filament bulbs. As an exception, our High Power LED car bulbs are as bright or brighter than most standard filament car bulbs. The light is distributed differently so they can appear brighter in some applications and not as bright in others, it depends on the size and shape of the bulb housing and reflector.

Most LED bulbs emit light like a flashlight, all out the end. Regular filament bulbs emit light from the end and all sides, so they will be better suited for some lighting applications than LED bulbs. This is the same reason why we do not rate LED car bulbs in lumens or watts, the numbers would be deceptively low because the light is measured from all sides and the end on standard filament bulbs but only from the end on LED bulbs.

What is the difference between Warm White and Cool White?

Warm white and cool white have two different correlated color temperatures which are measured in Kelvin. Warm white (2500K~4000K) resembles incandescent light bulbs, cool white (5000K~8000k) resembles fluorescent light bulbs.

                                                                                                        This Picture comes from Superbrightled

Which LEDs bulbs are brightest?

Our 18 and 45 SMD LED Tower bulbs are by far the brightest we offer. Some of our bulbs are available with 12, 19, 24 or 30 Standard LEDs, the more LEDs they have, the brighter they are. Filtering and sorting by Brightness will allow you to easily compare bulb brightness.

Are your bulbs standard size?

All of our Tail/Brake lights are the standard one inch diameter except for the 30-LED units. They are 1-5/8 inch diameter so please measure to make sure they will fit in your housings. All of our car bulb types have a "more info" button near them, click these buttons to see dimensional drawings and other specifications.

What is the difference between Narrow and Wide viewing angle?

Some of our bulbs are available with Narrow or Wide viewing angle. The Wide angle (approx. 100 degree beam) will light up more area but dimmer than the Narrow angle. The Narrow angle (approx. 15 degree) will illuminate a smaller area but brighter than the Wide angle. We also offer bulbs with some LEDs aiming out the end of the bulb and some radially mounted LEDs aiming out the sides of the bulb. These will provide a more complete and even light pattern on the vehicle lens.

We cannot recommend which type would work best in your vehicle because it depends on the size, shape and depth of your bulb housings. The Wide angle bulbs usually work best for most vehicles.

How do your LED bulbs achieve dual intensity?

All of our Tail/Brake bulbs achieve dual intensity modes by turning all of the LEDs on dim or all of the LEDs on bright, all of the LEDs are always lit when either mode is active.

If I install LED bulbs in the dash, will the dimmer still work?

Yes, LED bulbs will dim with your dash light intensity control.