Help me troubleshoot a Surefire 6P.

[Steve V.]

I have a Surefire 6P that I bought new a long time ago. I used it very little and ended up putting it in my vehicle. It had Surefire batteries in it. I rarely used it. I decided to check it a couple of days ago and it didn't work. I just bought some Streamlight CR123A lithium batteries. I put them in positive side toward the head and tried the light. It doesn't work. The light is in almost mint condition. There is no corrosion in the light and everything looks fine. I checked the bulb with a 10 power loop and the filament looks fine. Any ideas?

Thanks,

Steve

 

[LRJ88]

Have you checked to see so you don't have any gunk built up on some of the contacts over time? Bypassing the switch, giving any contact surfaces a good wipedown with alcohol etc.?

 

[lightfooted]

Did you tighten the tail cap down? I know that may seem kinda obvious to any flashaholic but...I don't know that you are one. I suppose it's possible that some corrosion may have built up inside on the springs at their contact points to prevent it from turning on so cleaning all of those surfaces is not a bad idea. I would just think that you might have cleared away enough of it for it to light when you changed out the batteries. I am assuming that all of the parts are original and thus we aren't trying to troubleshoot a faulty drop-in without knowing it.

 

[archimedes]

The original 6P is such a simple circuit, and each part can be readily repaired or replaced, that it should be fairly straightforward to troubleshoot.

1) test & replace batteries with known good cells (yes, again ... lol)

2) check, clean, and tighten all contact surfaces to ensure electrical continuity, including inspecting springs (eg, not overly flattened, bent or compressed, etc)

3) briefly bypass tail switch with a short piece of wire to assess that function

4) test and/or replace lamp assembly with known working lamp or LED dropin (visual appearance of filament integrity is no guarantee of proper function)

The easiest way to do most of this is if you have a working duplicate. Swapping out each part, one at a time, will generally isolate and identify the problem straightaway.

 

[bykfixer]

I use a digital volt meter set to ohms and "beep". Using pins instead of clips I find a spot to hold the positive and touch the light with the negative in various places to check for circuit flow. A beep means power flows to that point. And there have been times that what appeared to be a clean surface had a film on it that I could not see but interupted the circuit enough for the light to not work. I use Tarn-X but de-oxit or even rubbing alcolhol work too.

I wonder if the twisty switch may not be making proper contact for one reason or other. Or as in a lot of cases the filament looks intact but a slight disconnect has occured you just don't see without a magnifier. Bulbs don't aleays go poof in a grand way with filament all hanging like a broken wing. Sometimes they just quietly stop working.

Oh, and make sure the head is twisted all the way tight as well. If not both springs in the P60 may not be making contact as intended.
Sometimes the simplest things can be the hardest to figure out. :thinking:

 

[Steve V.]

The original 6P is such a simple circuit, and each part can be readily repaired or replaced, that it should be fairly straightforward to troubleshoot.

1) test & replace batteries with known good cells (yes, again ... lol)

I'll get another set today if I can get to the store. It's pouring down rain here.

2) check, clean, and tighten all contact surfaces to ensure electrical continuity, including inspecting springs (eg, not overly flattened, bent or compressed, etc)

They looked good but I doubled checked them and cleaned them with alcohol just in case.

3) briefly bypass tail switch with a short piece of wire to assess that function

I'm not sure how to do this. The switch on this is the twist to stay on or back it off a little to press the rubber button to activate momentary light.

4) test and/or replace lamp assembly with known working lamp or LED dropin (visual appearance of filament integrity is no guarantee of proper function)

I'll have to order one from Amazon. I thought about going to LED but I'm just going to use this light now when I tinker around the house so I'll probably go with original.

The easiest way to do most of this is if you have a working duplicate. Swapping out each part, one at a time, will generally isolate and identify the problem straightaway.

No duplicate available. I have three old Streamlights and one really old D cell battery light (not a Maglight).

 

[archimedes]

Some suggestions (including how to test the tailswitch) from SureFire, here ...

https://surefire.news/surefire-flashlight-maintenance-411/

 

[Steve V.]

I checked the tail switch as indicated in the linked article. Still no light. The batteries I bought have an expiration date of 2030 and I checked them both with a multimeter and they are good. I guess it has to be the bulb.

 

[Christoph]

Burned out Bulb? It is a hot wire correct?

Chris

 

[ampdude]

I checked the tail switch as indicated in the linked article. Still no light. The batteries I bought have an expiration date of 2030 and I checked them both with a multimeter and they are good. I guess it has to be the bulb.

It could very well be from what has been described.. I would put another bulb in. Very cheap troubleshooting there.

 

[Steve V.]

I really appreciate all of y'alls help! I'll let you know what the end result is. I may just get and LED bulb for this light. Maybe the Malkoff M61. Would anyone have an opinion on this one? https://www.amazon.com/dp/B072ZW5F23/?tag=cpf0b6-20

 

[peter yetman]

Don't waste your money, save up for a Malkoff. You could also use a Sportac drop in, which will save you a bit and still give you good service.
P

 

[lightfooted]

I checked the tail switch as indicated in the linked article. Still no light. The batteries I bought have an expiration date of 2030 and I checked them both with a multimeter and they are good. I guess it has to be the bulb.

If you have a multimeter you can test the bulb y'know...just use continuity mode and put one probe on the center spring and the other on the outside spring. If it doesn't beep or whatever it does, then yes...your bulb is out.

Also: an XM-L2 LED does not emit 1200 lumens...not even out the front. I recommend any of the above drop-ins plus ones from Lumens Factory.

 

[Steve V.]

I just checked the bulb with a multimeter. No joy. Time for a new bulb.

 

[bigburly912]

I have a "few" spare YC-3 6v lamp assembly if you want to keep from going LED. Just pm me your address and you can have it if you decide to go that route