The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Auto Side Marker Bulb: FAIL

    Six years ago I replaced the W5W incandescent front side marker bulbs in our 2015 Subaru Forester with amber LED bulbs:

    Side Marker bulbs - failed adhesive
    Side Marker bulbs – failed adhesive

    The adhesive holding the LED PCB to the aluminum “heatsink” has fossilized and the strip on the right is peeling off (with the left one not far behind), which likely accounted for its loss of light output and flickering.

    Tearing it apart reveals the LED layout and what looks like a bridge rectifier or a big resistor (to fool the CAN bus?) on a tiny PCB jammed inside the shell:

    Side Marker bulbs - rectifier
    Side Marker bulbs – rectifier

    The other side of the PCB could be a buck converter:

    Side Marker bulbs - buck converter
    Side Marker bulbs – buck converter

    In round numbers, we’ve driven 18000 miles at an average of maybe 40 mph over those years; call it 450 hours. However, the side marker lights aren’t on unless the headlights are on; we do very little night driving, which means those LED bulbs are the usual crap.

    I replaced both front bulbs with a different design sporting two LED chips and we’ll see how long those last.