BAY15D car LED lamp

BAY15D LED bulb (1157, P21/5W): two light levels in one bulb

The BAY15D is a bayonet base with two contact points on the bottom, also known as 1157, P21/5W or 7528. One bulb has two light levels. That is why it is often used in the combined brake and tail light, and on some vehicles in a combined position light and indicator. Here you will find BAY15D LED bulbs in red, orange and daylight white (6000K and 6500K), for 12V and for 12-24V. There are also CAN-BUS versions with forced cooling. All bulbs are supplied in sets of 2.

What to look for when choosing

• Light colour per function: red for brake and tail lights, orange for indicators, daylight white where white light is required.
• Two levels: the BAY15D has a dim and a bright level, for example for tail light and brake light. After fitting, check that both levels work properly.
• Voltage: 12V for passenger cars, the 12-24V versions also for trucks, buses or campers.
• CAN-BUS: if your car's on-board computer monitors the bulbs, preferably choose a CAN-BUS version.
• BAY15D or BA15S: the BAY15D has two contact points, the BA15S (1156) has one. They are not interchangeable.

Will it fit your car?

Look at the bottom of the old bulb: two contact points and pins at different heights means BAY15D. Fit the bulb in the correct position, otherwise the two light levels will not work as intended. Do you get an error message after fitting, or does the indicator flash faster? Then we recommend a suitable resistor; see our LED resistors.

Laws and regulations

If you use these bulbs in brake, tail, position or indicator lights, the light colour and operation must meet the legal requirements. So check in advance whether use in your vehicle is permitted.

Looking for a different base? Also take a look at the BA15S LED bulbs, the T20 LED bulbs or all LED car lighting.

The tips on this page are non-binding advice; installation and use are at your own expense and responsibility.