Thread: I think I broke it...

Well, I had been given the guts out of some old Gen I interior light bar. The previous owner switched the + and - and let the smoke out. I took it and checked the LEDs and they seemed to be working ok. It just needed a new flasher unit. Fast forward a few months, I have a Whelen ULF44, and I'm working on rigging up these LEDs so I can connect them to the flasher. Well, I've spent the past few evenings soldering on extensions to each of the little 22ga leads. I hook them up to my bench-top power supply and BLANK. Very few of the LEDs are working. The ones that are working are very dim.


Did I somehow fry these lights during the soldering process? If I put a multi-meter across the solder pads of the LEDs I get (eventually) +12.71 VDC.

Oh crap...what are the odds that the circuit board in the original light bar had some sort of voltage step-down transformer?


IF, that is the case...did I just completely ruin them by hooking them to +12VDC?

Maybe its the opposite and you don't have enough voltage going to them.

Originally Posted by SireLite

Maybe its the opposite and you don't have enough voltage going to them.

I was thinking the same thing. LED's that are dim mean not enough volts are getting to it...if you blew one LED, they would all be if they were connected in series.

So, I did some more investigation last night...

I dug out the old guts to the light bar. This was one of those light bars that was split in two-halves with a pig tail between the two. Each half had it's own PCB and the other half is what fried. If I put +12V to the other side (the side that conveniently has the controls on it) then it fires right off.

So, that's what I did. I re-connected some of the light heads to the functional PCB and put 12V to it. 4 out of the 5 positions off that PCB worked. The 5th one was very dim. I switched some of the light heads around to check if it was the light, or if it was the board. No matter what light I put in that position, it did not work properly. But then when I moved it to a different position it worked just fine.

I checked the voltage across the malfunctioning position on the PCB and I got +12VDC so now I'm really stumped.

Now I'm thinking that the individual light heads are not bad...BUT what is going on?

*edit* well, I put the working half of the PCB in "California mode" with the steady-burning modules. I checked the voltage across those and got 15.71VDC! You guys were right! There is a 3V step-up!

Now, I need to source some DC to DC converters. At this point it's not even about the light. I'm sure I should probably just buy something off the shelf. But now I'm determined to make this thing work again just to say that I did it!

Originally Posted by vonirkinshtine

Oh crap...what are the odds that the circuit board in the original light bar had some sort of voltage step-down transformer?


IF, that is the case...did I just completely ruin them by hooking them to +12VDC?

Can I ask what bar/light this circuit board came from?

I'm thinking a Slimlighter clone. With Axixtech type switches.

Originally Posted by Zapp Brannigan

Can I ask what bar/light this circuit board came from?

No idea. Both the LEDs and the PCB are labled "Juluen".

Originally Posted by vonirkinshtine

No idea. Both the LEDs and the PCB are labled "Juluen".

Yup, Juluen = Axixtech

It's a stealth Visor.

They came in both Xtreme (linear) and and gen 2/1 models which you have. Looks like your missing one LED module.

JULUEN ENTERPRISE CO.,LTD

You might be able to get parts off any Axixtech/Brookings Dealer.

Yup! Stealth Visor - that's it!

Hmm...spare parts? I guess I would entertain the idea, but I thought Axixtech went bye-bye?

Well, let this be a call to anyone here that is an Axixtech parts dealer! I need a quote!

Axixtech is still going. Loads of members on here Sell Axixtech Products.

it's just lightningX that stopped selling them.

Originally Posted by SireLite

Axixtech is still going. Loads of members on here Sell Axixtech Products.

it's just lightningX that stopped selling them.

Oh...ok, I gotcha.

That bar is from the Gen 1 Stealth Visor. The Gen 3 versions put out about 30 Volts per head, so had you connected it to that circuit board, you would have fried your modules. As for parts, you are not going to find any from any dealer. I've repaired a few bars that people have wired up backwards and the dc-dc converters are not easy to find. You have to find compatible components, and that's only when you know which ones are defective.

On the bad board, check the large 6A diode that goes across from positive to ground. This usually blows (as designed) to prevent the rest of the bar from going up in smoke. If people would just use a fuse when testing a light, the fuse would blow before the boards do.

I know you're dying to fix it, but you'll need to check every component and traces on the board to figure out which components are bad. My last one had diodes, capacitors, resistors and dc-dc converters that were blown. There were several traces that were fried as well which required new lines to be run. It was a PITA to fix, but she's back up and running again like new.

Hope that helps.

Tony

Tony, thanks for the info. Between the DC-DC converters and the fact that I'm still not that great with a soldering iron, I think I'm going to give this one up.

If I spend 2 more weeks and however many more dollars I'll still only end up with an old Gen I light bar. Hell, by the time I get everything put back together it may or may not work!

The UFL44 is still NIB so at least I can get [most of] my money back for that by selling it here.