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Auto Parking Light LED Bulbs: FAIL

2026-04-06

Electronics Workbench Home Ec Machine Shop

Rants, Repairs

After about eight years and a similar failure last year, this came as no surprise:

White W5W Parking Light – failed chips

It’s a W5W “parking light” in the same fixture as the melty halogen high-beam bulbs (used as daytime running lights at half power), so it gets toasted on those occasions when we drive somewhere.

The adhesive holding the LED strip to the aluminum shell fossilized and came loose:

White W5W Parking Light – failed adhesive

Now that I know what to look for, I’d get LED bulbs with chips soldered directly to the PCB, although it’s not obvious what holds the PCB to the aluminum frame.

I reinstalled the original incandescent bulbs.

Comments

6 responses to “Auto Parking Light LED Bulbs: FAIL”

2026-04-06

Mick King

but but but LED will last forever! will save the world!

Reply
1. 2026-04-06
  
  Ed
  
  That pesky glue keeps getting in the way of World Domination!
  
  My box of CFL bulbs, many of which probably still work, goes to the next hazmat collection event. :sigh:
  
  Reply
2026-04-06

brentatedsblog

The design of the LEDs for automotive bulb replacement is like it was all done by a college sophomore.

Most make every mistake there is. A few get it right.

I have started to look for ones that are rated 6v~30v those must have a switcher on them, right?

Example: Ruiandsion LED Turn Signal Lights AC 6-30V Non Polarity

I needed the 6v for my old 1946 truck, but I think they might be better bulbs in general. Time will tell.

Reply
1. 2026-04-06
  
  Ed
  
  Sort of like all the handy little PCBs have circuits taken directly from the IC’s App Note.
  
  The 194-style bulbs tout their “intelligent IC” circuitry, which AFAICT amounts to a diode bridge, so they may run the LEDs at four or five times the 6 V current at the high end of the voltage range. :sigh:
  
  Reply
2026-04-06

brentatedsblog

I put an “XC1156-5730-17-W-6-30V” on the bench:

(which might be here: https://www.ruiandsion.com/Ruiandsion-2X-BA15S-1156-LED-LAMP-FOR-CAR-BULB-TAILLIGHT-BRAKE-LIGHT-360LM-WHITE-WW-p4208574.html)

(or help the starving billionaires here)

The “6v” is quite hopeful, but it does look like constant current (sorry for the coarse X resolution):

That is not say there are not a myriad of other ways it can fail — but it at least seems to be insensitive to voltage.

Reply
1. 2026-04-06
  
  Ed
  
  It runs at constant power, rather than constant current, so it doesn’t get hotter at higher voltages!
  
  Now, having it get dimmer at higher voltages may come as a surprise, but there’s some good sense in there. :grin:
  
  Reply