Need help repairing Ultrafire U4-MCU (Replacing Pill)

Have never ordered from them, but I am excited that i've found a reliable and quick US dealer! Can't wait to get the parts! I see they are in NY, so I should be able to get them quickly and get this light put back together :)

Sorry guys, just thought of 2 last questions. Can I use computer Cpu thermal paste that I have for the led? And also, to switch the led to the xm-l in my working model of this light, do I have to change the driver also?

You don't have to change the driver but it might be brighter if you do it depends if it is direct drive on high try it out and test it with a DMM. Computer thermal paste is perfect, same stuff basically.

Alright my parts shipped yesterday and will hopefully be here tomorrow. I noticed on the damaged driver that there are 3 wires, pos, neg, and what looked like a ground to the pill. Will the new driver have a spot for this ground wire? And will it tell me where to connect it?

Anyone?

Hey Civic,

The ground to the pill is the negative electrical connection to the battery. Your replacement driver won't have that (most don't). Instead, you'll find that a copper trace has been left around the circumference of the board, on the battery-facing side... just bridge this to the pill with a drop of solder, and you'll be laughing.

Good luck!

Thanks :) It took a little modifying to make the new driver work in the old pill, but it works! Only gripe is that the new LED doesn't meet up flush with the hole in the reflector like the old one did, because it's much smaller. And I was unable to re-use the plastic ring that went between the pill and reflector because it used to fit around the old LED and it is too big for the new one, but it doesn't look like the wires from the LED have any chance of touching the reflector. But oh well, my light works again and that's the important part! Thanks for the help!

Glad it worked, man. Plus, now you've got an excuse to slip in a new LED someday when you get bored... :P

You might be able to get away without an isolation disk, but if find you're having electrical shorts, you can often use those hole-reinforcement disks from a stationary store or a nylon/kapton disk from a hardware store.

Take care!

Awesome glad it worked out for you. Make sure you at least put some electrical tape in the shape of the plastic ring on the reflector, if it hits the wires it will cook something for sure. I love it when a broken light works again.

08CivicSi can you put some pic please

Sure, what would like pics of? Beamshots?

Give pics of your modded light with the other C8 and some beamshots of both lights.

I will do this tonight for you, sorry i've been really busy with work! I did measure tailcap current just for the fun of it earlier today and got

Batt - 18650 @ 4.1V

1.39A High

430mA Mid

70mA Low

I was surprised high current is so low, but maybe it's my meter? Oh well light is awesome anyways and does not get very hot so i'm thrilled with it. Will attempt beamshots when it gets dark

I can confirm that the coupon was still working as of Saturday, October, 09,2011.

It should be pulling 2.Amps with the XML led. Fully charge the battery and compare with the non XML light for current draw.

Thanks How2, I will charge and retest the light tonight. I am using a really cheap multimeter, I don't know if that might make a difference or not. Here are some beamshot pics that I finally was able to take last night, hope they are good enough :).

Pic of the LED --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9193Medium.jpg

Day Shot - Place 1 --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9195Medium.jpg

Low --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9203Medium.jpg

Mid --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9204Medium.jpg

High --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9205Medium.jpg

Day Shot - Place 2 --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9198Medium.jpg

*Low was not visible*

Mid --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9208Medium.jpg

High --- http://i69.photobucket.com/albums/i55/icemurder/IMG_9209Medium.jpg

Sorry, couldn't figure out how to post images without links! I would post pics of the spare lights beamshot for comparison, but the stupid LED dome thing fell off of it too! Guess i'll replace that one with an xm-l when i get around to it!

In order to post the image here.

You have copy the image location. Put your cursor over the photo the Right click then choose copy image location. The in this site you click the add image(tree) paste the image location.

What driver did you use to drive the XPG?

this one http://www.shiningbeam.com/servlet/the-133/3-dsh-Mode-Regulated-Circuit-Board/Detail that you suggested for me

also got the xp-g LED that you suggested, very happy with both so far

Your driver is working fine. When you get the XML you will see the difference.

Twice as bright if power at 3Amps.