Headlamp teardown: Silva Cross Trail II

The Silva Cross Trail II is the successor of the Silva X-Trail and Silva X-Trail Plus.
See: http://silva.se/product-family/x-trail

The main different is ofcourse the 250 Lumen instead of 145 Lumen of the old X-Trail.

However a cool feature was the usability of Lithium-IO battery packs instead of 4xAA batteries when you buy the Plus instead of the standard version.

Well, this option was gone with the new Silva Cross Trail II, so I was wondering if the new one is still capable of using higher voltage Li-IO battery packs.

To get to the main board, you have to apply a good amount of heat the metal ring of the case. The ring is not screwed on, so you can just pop off after a while. The same technique with heat and gentle pulling can be used with the plastic ring after the meat ring and the button rubber is removed.

Apply heat to release the glue

Before you can pull out the main board, you have to remove the power cabling on the opposite side. First remove the silicone blob, open up the cable restrainer and then desolder the cabling.

The power cables after removing the strain relieve. The "dirty" stuff is the removed silicone

Then you can gently pull out the board.


On the left side you can see the microcontroller PIC16F505 which uses as input the switch on the left side and controlls the two 5mm LEDs for surrounding light the battery indicator LED (below the middle center hole) and the main high power LED in the middle of the board.
On the right side you see an active step down (Buck) converter (TPS62110), which works with input voltage of 3.1V to 17V. The TPS62110 is able to provide up to 1.5 Ampere.

The high power LED in the middle could be CREE XP-G . The measurement I did:
The base of the 3,45mm x 3,45mm
The dome is 1,25mm high (without base plate)

The lens has a diameter of 18mm and is 10mm high. The holding clips which fit into the main board are all exactly 10mm away from the center LED.

All Photos:


  1. Hi
    Very helpful page.
    Mine got water inside and I’m trying do dry it. Do you recomend to disassembly it? Was the reassembly successful in terms of stancheity?
    Which heat source you used to remove the ring?
    Thank you

    1. Hi Albert,

      I used a standard heat-gun (like a hair-dryer, but can achieve higher temps). That worked pretty good.

      If you ensure that the powercables are sealed again, it is still insulated against water.

      Good luck,

  2. Hi, I have the same head lamp and are really satisfied with light. BUT to it looks like Silva has a problem with the battery box, the cable out breaks some how. I’m on my thrid battery box. I see that you found the buck converter to accept 3,1 – 17 Volts. Does this mean that I can build a battery box with 18650 cells (2s2p or something) and just plug it in?

    1. Yes, that “should” mean it. It is exactly what I was trying to do, but I never completed this rebuild as I had to move my home and other things in life came across these plans 😉

      I planned to use the usual China-bicycle light powerblocks, which also use 18650. Their power-plugs are made well enough against wet and damp conditions and cheap and easy to get.

      Please keep me updated on your conversions.


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