I'm looking at these LED replacement bulbs for the interior of my sweet conversion van. I'm looking for a more efficient alternative to the BA15 bulbs that are in there already. These bulbs appear to be really bright, and I can't seem to find a lower lumen LED light in warm white. I'm wondering if it is possible to unsolder or intentionally damage some of the LED panels to decrease the brightness of the overall bulb, or if that will disrupt the entire bulb.
These assemblies have 18 LEDs on them, which I guess are connected in series of 3. All series are in turn connected in parallel. Desoldering 1 LED will disable the whole 3-LED block.
Try desoldering one of the LEDs and test to confirm.
You could wire a resistor in series with the base. The lamps are claimed to be 2W so they should draw around 170mA from the 12V bus. Try about 10-50 ohms 1W to get the brightness you want.
Of course you will no longer be able to safely install an incandescent bulb, in fact doing that could cause the resistor to get dangerously hot. You could add a small resettable fuse (polyfuse) to prevent that situation.
As a bonus, the lamps should last much longer, especially in a warm climate. They are typically driven to within a millimeter of their lives because that saves the manufacturer money.
What you likely have here are 6 strings of 3 LEDs connected in parallel.
If you disconnect one set of 3 that should work.
If there were an LED driver then the current would be diverted to the other 5 sets.
> At this price point I am doubting there is a driver.
Each panel is likely independent of the others
Remove one LED from one of the panels.
I'm willing to bet only that one panel goes out and everything else will be fine.
If it dies then dissemble it to see what's under the hood.