Brightest 66 SMD 4014 SwitchBack DRL Dual-Color LED Turn Signal Bulbs – White DRL Amber Indicator

One bulb, two jobs. Steady white while you drive, amber the second you indicate.

The PY21W your car left the factory with does exactly one of those, and only when the stalk moves. This TecUpdater switchback squeezes 66 high-intensity 4014 SMD chips into the same shape, so the socket that used to give you an orange flash now also gives you a 6000K white daytime running light. White drops out while the indicator works, then comes back by itself once you cancel. On a car that never had DRLs in the showroom, this is the cheap and honest way to get them.

How it goes in:

1. Check the base before anything else. These are made for PY21W / BAU15S / 1156 and T20 / 7440 / W21W sockets, and fitment follows the socket, not the badge, so European, Japanese, Indian and American cars are all fair game as long as the base matches.
2. Get behind the indicator housing. Usually that is a quarter turn of the bulb holder, reached through the engine bay or by peeling back the wheel arch liner.
3. Twist the old bulb out, twist the LED in. Turn signal duty is plug and play, and CANBUS is built into the bulb, so no hyper-flash, no bulb-out warning on the cluster, no resistor bricks dangling off the loom.
4. Tap the supplied wire for the white side. DRL activation needs one extra connection to a suitable feed. It is a tap, not a cut, and no major modification to the car is involved.
5. Test with the liner still off. Ignition on, white should sit steady. Indicate, and it should flip to amber, then return to white when you cancel.

Numbers worth knowing: 12V DC, 4.2W in white DRL mode and 25.2W flashing amber, 360 degree spread so the light shows from an angle and not just head on, an aluminium housing over a high-efficiency PCB to pull heat off the chips, a vibration-resistant build, and 30,000 hours plus of rated life. Applications are the obvious ones: a front turn signal upgrade, a DRL conversion on a car that never had them, or a retrofit or custom build where you want two functions out of one hole. Supplied as a set of two, returns eligible as per policy. Skip the DRL wire and you still own a perfectly good amber indicator bulb, just with half of it doing nothing, so if that one extra connection is a step too far for you, buy something simpler.

Technical details

Vehicle fitment

A switchback only earns its keep if it matches the indicator socket your car actually uses. The groupings below are drawn from owner reports and parts guides, not a factory list.

Hyundai

Creta, i20, Verna and Xcent are usually listed with the PY21W/BAU15S amber indicator.

Maruti

Alto and Baleno commonly show that same offset-pin bayonet. The Dzire (2010-2021) is the odd one out, reported with a WY21W/7440 wedge for the indicator and a straight-pin BA15S at the reverse lamp — a base also found on plenty of older Maruti, Tata and Mahindra rear units.

Kia

Seltos is often found on the PY21W amber list.

Two mix-ups are worth watching for. BA15S pins run straight, BAU15S pins sit offset, and the two never swap. And 7440 carries one filament where 7443 carries two — same hole, different wiring. Pull your existing bulb out, read the code printed on its base, then order.

Drawn from public charts, not yet cross-checked trim by trim. Facelifts in particular differ, so confirm with the bulb in your own car.