I'm having a problem with my 120P

William_H

Newly Enlightened
Joined
May 12, 2006
Messages
58
Location
DFW, TX
Just thought I might run it by you guys and see if there's a quick fix that I'm overlooking before I see about sending it back to Novatac.

It's always worked perfectly for me until recently. I took it out and clicked the button and...nothing. I clicked a couple more times and realized it would stay on if I held down the button. But very dimly. So I changed to a fresh battery and got the same thing. It will only stay on as long as I hold down the button and again, very dimly.

Is something you guys have experienced?
 
Try cleaning all contact surfaces in the light, including both ends of the battery tube as well as the surfaces it treads against in the tailcap and the light engine. It really sounds like you just need to clean it.

Edit: While you're at it, also check that the retaining rings in the tailcap and in the light engine are tightly screwed in.
 
I agree with the previous post. Make certain the tailcap threads and contacts are clean and then screw the tailcap ALL the way in. This will probably fix things. The low brightness could just be a low setting. The light is capable of outputting as low as .08 lumens.
 
Did you accidentally set it to the tactical momentary mode? Just a thought.
 
Check the light for tightness. if the retaining ring holding the guts in the head becomes loose this issue can come up. Simply tighten it Dow. Also check the retaining ring in the switch module.
To tighten the ring in the dead correctly if loose turn the bezel a 1/4 turn to loosen it. then tighten the retaining ring then tighten the bezel. if done correctly this should solve the problem forever.
That is IF you have loose retaining rings.
Yaesumofo
 
Yes, do all of the above mentioned details ... this is a highly sophisticated light, and many of them require a bit of "tuning" at first to optimize their performance.

You didn't mention what type of battery you are using. If you've changed to a rechargeable battery, you might need to do a battery reset.

While you are cleaning the battery contacts and threads, be sure and clean both ends of the big spring in the battery tube. That spring provides the pathway for all of the operational commands from the tail switch to the microchip in the head. Also clean any place where the ends of the spring makes contact. You could even try GENTLY and CAREFULLY stretching the spring... just a TINY BIT to help ensure good contact at both ends.

The other thing to try is to remove the battery for 5 minutes, then reinstall it and do a factory reset, which is mentioned in the instruction manual. Do understand that it can be a bit tricky to do. It took me quite a few attempts at first to understand the timing of screwing the tube back together, waiting for the dim light to come on, then quickly holding down the button and waiting for it to cycle... so just do it until your sure you've completed the sequence correctly.

There is a good chance that if you follow the tips presented in this thread that you will fix the problem. My 120P needed a tune-up when I first got it last August, but since then it has been used almost every night at work with virtually no service, and no glitches.

If you have any more specific questions feel free to PM me. Good luck.
 
You could even try GENTLY and CAREFULLY stretching the spring... just a TINY BIT to help ensure good contact at both ends.

Yes, try all of the above, but about that spring...

It's critical to making contact from end to end and to the case, so it is often an issue to look at.
However, you don't want to stretch that spring, you want to sort of uncoil it. By gently unwinding it just a little, you increase the diameter of the spring so it will make better contact with the inside of the tube. Also unwinding it a little serves to increase it's length as well while just stretching it may actually decrease it's diameter.

Once a Novatac has been "tuned up" and everything is in perfect contact internally, you'll likely never have to touch it again.
 
I don't believe the spring needs to touch the inside of the battery tube, the inside of the tube is anodized(insulated). The spring makes contact between the bottom plate of the tail cap and the top plate of the head(IIRC it carries the switching signals from the tail cap to the MCU).

I would clean the threads with alcohol (Deoxit it you have it) and make sure the two retaining rings are tight.

If none of these suggestions help contact Jessie at Novatac, they have excellent customer service.
 
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I don't believe the spring needs to touch the inside of the battery tube, the inside of the tube is anodized(insulated).

While I don't personally know the importance of the spring touching the inside of the case, I do know that expanding it in the way I described came directly from Novatac when I had a question about my own 120P.
I only "assumed" that the purpose of expanding the spring was to make contact with the inside of the case. All interesting stuff...
 
I've always assumed that stretching the spring caused more pressure and therefore better contact on the ends of the spring. If they were using the body tube as electrical contact, it shouldn't need a spring, it would go right through all the threads.
 
If they were using the body tube as electrical contact, it shouldn't need a spring, it would go right through all the threads.
They (Novatac) are using the tube as an electrical contact, but a different one. One that should be electrically isolated from the big spring.
 
I love my 120p, but also occasionally have strange difficulties- similar to what you have described. I find that they usually happen when a battery is very low. (123 primaries.)

I think all the ideas for "tweaking" your 120p are good ones, and everyone who owns one should do these things to "set up" the light. Never underestimate the value of the factory reset, however!! The two or three times I have run into trouble with my light, it has been fixed by the factory reset.

Yes, a $150 light should require less work to keep it running. But I also try to remember that this is a fine, flexible, capable piece of gear. I just keep telling myself, "Porsche, Porsche, Porsche.......Needs lots of work, but it's as good as it gets when its working!!:thumbsup:

Good Luck!!
 
After reading this thread yesterday i gave my 120P an "oil change" Charged the battery, cleaned and lubed threads and o-rings, deoxit all electrical contacts, put it back together and i swear it's brighter, maybe it's just happy :)
 
After reading this thread yesterday i gave my 120P an "oil change" Charged the battery, cleaned and lubed threads and o-rings, deoxit all electrical contacts, put it back together and i swear it's brighter, maybe it's just happy :)

Just make sure to do a battery detect test when putting in a freshly charged battery.
 
Does this apply on T models?
I only have the 120P, but I'm pretty sure that the Battery-Detect-Reset would be required on all 3 EDC models when changing between a primary and a rechargeable battery. I believe it is used to set the level when the light begins stepping down as well as the cutoff point to help keep from over-discharging a lithium-ion battery.

It is important to note that when changing to a rechargeable battery the battery should be fully charged before doing the Battery-Detect-Reset.

By the way, in post #7 above, Zenster referred to uncoiling the spring rather than stretching it. I hadn't considered it, but this is probably a preferred method for achieving the same result..... increasing the length of the spring a bit to help it make more consistent contact at both ends... but doing it in a way that does NOT decrease the diameter.

I think the reason for this is that you don't want the spring to be so tight as to be wound tightly around the battery, because if it were, then if the light took a sudden jolt which caused the battery to move a bit, it might cause the spring to lose contact. So, you want a loose spring which floats independently from the battery, maintaining contact at each end under all conditions.
 
By the way, in post #7 above, Zenster referred to uncoiling the spring rather than stretching it. I hadn't considered it, but this is probably a preferred method for achieving the same result..... increasing the length of the spring a bit to help it make more consistent contact at both ends... but doing it in a way that does NOT decrease the diameter.

I think the reason for this is that you don't want the spring to be so tight as to be wound tightly around the battery, because if it were, then if the light took a sudden jolt which caused the battery to move a bit, it might cause the spring to lose contact. So, you want a loose spring which floats independently from the battery, maintaining contact at each end under all conditions.

You know, I'll bet you're exactly right. When I was told by the people at Novatac to "open up" rather than stretch the spring that way, I probably jumped to the wrong conclusion as to why by assuming it was make better contact with the inside of the body (they didn't explain WHY to do it that way, just WHAT to do).
But your take on why it should be unrolled rather than just stretched makes perfect sense because it would be aggravating for the battery to be stuck in the spring all the time.

Good call! :twothumbs

But whatever the reason, once I did that, I've never had any kind of erratic behavior since then, even with an almost depleted battery. So I guess that making contact on both ends of the spring is the critical part, and it probably wouldn't hurt to clean up the ends of the spring with a pencil eraser once in a while either.
 
Just thought I might run it by you guys and see if there's a quick fix that I'm overlooking before I see about sending it back to Novatac.

It's always worked perfectly for me until recently. I took it out and clicked the button and...nothing. I clicked a couple more times and realized it would stay on if I held down the button. But very dimly. So I changed to a fresh battery and got the same thing. It will only stay on as long as I hold down the button and again, very dimly.

Is something you guys have experienced?
Bump to find out if the problem has been resolved.

Woot, flashaholic status!! :)
 
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