can anyone identify this?

[chris846]

front offside parking light stopped working, bulb okay, found an open circuit between the connector and the lampholder - turns out to be a small electrical component inline in the +ve grey wire to the bulb. Looks like a resistor but the equivalent component on the passenger side, (which presumably still works,) shows zero ohms, plus the voltage at the pass side bulb is 12v. Removed the duff item and shorted the wires together, the bulb now works fine, but I still get the bulb error message on the dash.
Any ideas what this doohickey might be?
thanks

 

[chris846]

well it was just a ceramic pellet with a silver coating - the coating was burned away. So I guess it was just a fuse.

Looking elsewhere for the fault, I have error free LED bulbs for the parking lights, they both work, but the one that triggers the fault message measures 220 ohms, the 'good' one measures 110 ohms. They were bought as a pair and have worked fine for months.

One for the electrical experts - do these 'error free' LEDs have a ballast resistor in parallel, so's they flow as much current as a filament bulb. Could that mean that my faulty LED buld has lost its ballast resistor - so it still lights up, but doesn't flow enough current to mimic a filament bulb?

 

[Ted]

Are you measuring the resistance on the bulbs with the same polarity on the dmm leads? The LEDs are semiconductor devices and will pass current when forward biased, so if you want to check actual resistance, ensure the led is reverse biased.

 

[chris846]

hadn't thought of that
checked them again, one of the pair of bulbs measures 110 ohms both ways, the other measures 220 ohms both ways...?

Thinking on, these LED bulbs can't contain a straightforward 5w ballast resistor - they don't get hot.

Think I'll just buy another pair of bulbs.