19 November, 2011

Petzl Myo XP repair

My first headlight was the Petzl Myo XP and I loved it from the beginning. Very well designed and build with little things to pick on.

I was pretty amazed when after 1 year of use my headlight broke down experiencing cable problems on the side where the cable enters the light head. Didn't thought much about it and put it all on a bad production sample, just returned the product to the store and got a brand new one instead. I've got mine from a local supplier, Himalaya, having luck on my side as there guys are big and serious about their business with all interests in keeping a good name about the products they promote.

All was back and track again till 1 year after when this 2nd headlamp failed with same symptoms. This time I was more than intrigued and determined to get tot he bottom of it my own way.

There's nothing you can't do with the right tools so in no time it was all pieces on my worktable. As I was anticipating, the good design from the outside was found inside as well. The LED chip is mounted on a separate PCB that has an extra aluminum radiator for efficient heat dissipation. Even more, a thermal probe is mounted on the heat-sink for thermal shutdown protection.
The LED chip looks like a Cree product but I might be mistaken. All looked fine with the solder points so with a multimeter found my problem to be inside the cable. Only solution now was stripping it apart little by little.

Need I say my surprise when finding the inner conductors? I couldn't believe my eyes, finding the wires in such a bad shape in such a high overall quality product. It looks like the wires suffered severe aging problems from low temperature exposures, at least that's the only thing that makes sense to me. They isolation layer lost it's elastic properties and cracked all around in multiple places. One of them got more mechanical stress than the others and that's how the electrical link failed.

The only thing I could do in this case was to cut away the most exposed part of the cable and resolder it to the PCB. Of course it got shorter in the process, of course I didn't solve the problem, just the effect but for now it will have to do.

UPDATE: Another Petzl Myo XP repair


  1. Salut! Am si eu aceeasi problema cu un MYO Rxp, si nu reusesc sa il deschid. Eventual, ai putea sa ma ajuti cu vreo idee?


  2. din cate stiu eu rxp-ul este constructiv similar cu xp-ul, deci dupa desfacerea celor 4 suruburi de pe spate se poate indeparta capacul spate. nu-i decat o problema de a avea surubelnita cu capul potrivit

  3. Hi! I have the same problem, but i do not know, how can i disemssemble the body of headlamp. Because i am afraid that i will break the two joints which hold body of headlamp. How is the haedlamp fixed to joints ? How can i disemssemble it, to avoid damage?

  4. if you have the right screwdriver then all you have to do is remove the 4 locking screws and the back side will come off without affecting the two joints

  5. Today, I'm adding myself to the list of Myo XP crappy cable victims.
    But thanks to your blog page, and thanks to some patience, I just replaced it in a couple of hours.

  6. salut. am un Myo 5 si cred ca tot in corpul lanternei e problema. m-ai putea sfatui in legatura cu desfacerea? mi se pare destul de complicat si nu vad nici un surub. merci anticipat

    1. salut. din pacate nu am vazut niciodata un Myo 5 de aproape si nici pe net nu gasesc poze cu detalii. Oricum, ca principiu capsulata nu este deci un mijloc de a o desface trebuie sa fie.

  7. Do you know the torx screw driver size?

  8. it's either metric T1.5 or impertial T5

  9. Very helpful thanks. I have the same issue.

  10. Hey , do you have any knowledge about driver module . actually I am a student and gathering some information about controlling modules.

  11. Ditto the brittle cable insulation issue. Fatal choice of material for an otherwise great lamp. And after 3 yrs Petzl won't cover.