D3 Rear indicator LEDs keep blowing

audifin · #1 12th August 2015, 10:23 AM

Back in June my left side rear indicator stopped working, too many LEDs had blown. I replaced them all and it worked fine for about 3 weeks, then they were blown again. I thought maybe I had bad batch of LEDs or something and replaced them again, but now they've stopped working again...

So I wonder if the "control PCB" is broken and is now frying the LEDs? Has anyone had similar problem?

I replaced the rear light LEDs about a year ago and have had no problems whatsoever.

Conquistador · #2 12th August 2015, 10:32 AM

When you say replaced them, do you mean opened it up and fixed it or just replaced the whole light unit?

audifin · #3 12th August 2015, 10:35 AM

I opened it and soldered new LEDs.

Delboy · #4 12th August 2015, 10:44 AM

Check the current limiting resistors on the circuit, I still have the pcbs from my old lights, the passenger side was on its way out with blown leds and the drivers side was fine IIRC.

audifin · #5 12th August 2015, 10:55 AM

Quote:

Originally Posted by Delboy

Check the current limiting resistors on the circuit, I still have the pcbs from my old lights, the passenger side was on its way out with blown leds and the drivers side was fine IIRC.

Thanks Del, any advice how to check them? i.e. can I measure them on the board or do I need to remove them? From memory there are about half a dozen connected in parallel.

Delboy · #6 12th August 2015, 12:27 PM

You should be able to measure the resistance through them by connecting the multimeter on either side set to ohms hopefully they will Al be the same resistance.

audifin · #7 16th August 2015, 11:12 AM

Finally managed to remove the lights again. There are 5 resistors connected in parallel, so they can't be measured individually on board. However, I removed both sides and both measure 1.6ohm with my multimeter. Colour code is Blue-Gray-black-silver-brown, which means 6.8ohm, i.e. 5 in parallel should be 6.8ohm/5 = 1.36ohm. Close enough I guess and as both sides return the same result, I believe the resistors are fine.

Del, did you say you have old PCBs, do you have the main PCB too? Would you be willing to sell them?

Thanks

Delboy · #8 16th August 2015, 11:37 AM

I believe I do, will need to have a root around in the shed, I'll let you know

audifin · #9 18th August 2015, 02:07 PM

Thanks Del, much appreciated.

Delboy · #10 18th August 2015, 04:02 PM

All i could find was one pcb, the shed is like a tip at the moment though.

If your badly needing them I could turn the shed out tomorrow.