It seems like this is a common problem with these lenses, the zoom gets stuck at 17mm with about 2mm of play (zoom movement). This problem is all due to a loose single screw on the inner lens assembly, sounds simple to fix, doesn’t it?
The challenge is trying to get to this single screw, which involves the separation of the lens into over 10 components, and the removal of about 20 small screws. Hopefully this guide will make the disassembly job a whole lot easier.
First, a reminder of what the lens looks like.
Turn the lens on its side with the connection contacts closest to you. There are 2 tiny Philips screws to remove.
Balance the lens on its front with the metal lens screw lock ring visible. There are 4 small Philips screws to remove.
The metal ring can now be hinged apart. This next step is the most difficult. The inner black plastic ring is connected to the metal outer ring with 4 plastic clips in the inside. By pushing the clips towards the center, the black plastic ring can be removed from the top of the metal outer ring. Much care is needed due to the ribbon cable still being attached to the connection contacts allowing for a gap of roughly no more than 1cm.
Once the inner black plastic ring is removed, the outer metal screw lock ring can be removed, exposing the PCB protected by a black plastic housing.
Disconnect a single pressure ribbon cable attached to the inside of the black plastic housing which will then allow for its removal exposing the PCB.
Disconnect the 5 ribbon cables from the PCB. 2 are pressure connected, 2 with a hinged clip and 1 with a pressure clip. Unscrew a single Philips screw allowing the removal of the PCB.
Remove the 5 screws (circled in red) holding the outer black plastic ring allowing the remove of the black plastic ring. Then remove the 3 inner screws (circled in blue).
Turn the lens over and remove the rubber zoom grip. It can be removed by inserting a very thin screw driver under the rubber and working your way around.
With the rubber zoom grip removed, rotate the lens until you find a black rectangle sticker, peal this off to expose some contactors.
With a Philip driver, unscrew the contactors. I actually performed this when reassembling the lens and slightly damaged them. It is better to remove them at the start to prevent this.
There are 3 screws sitting on small metal tubes between a groove, finally remove these.
With these removed the inner lens portion can now be removed from the outer casing.
You now have access to the problem screw(s) that need tightening. Once tightened, add some Loctite or nail-polish to stop the screws becoming loose again.
Some do’s and don’ts
- don’t remove the front lens sticker or 3 screws behind it.
- don’t remove the zoom sticker with m/ft increments.
- don’t touch or disassemble any of the focusing ring!
- do keep your UV filter on the lens, you can still remove the rubber grip with it on.
- do make sure the focusing pin between the inner and outer len is in place.
References
- FixYa post by Gert Jan [fixa.com]
- Canon EF 20-35mm f/3.5-4.5 USM Lens Repair [photo.net]
Tags: Canon, disassembly, EFS 17-85mm, lockded, repair, stuck, zoom
Hi,
I thought it was the Californian dunes sand that blocked my zoom lens: no! I repaired it with your help.
Thanks, Arndt
My lens has this problem and the repair guy asked more than the cost of a new one to repair it !
I this works I’ll make a suitable donation to charity on your behalf
My lens jammed at 60mm, and was going to follow this helpful guide. First I took off the rubber zoom grip, I notice one of the screws protruding more then the other, it was easy to tighten with a screwdriver through the gap without a full dismantle described here. It would be nice to be able to apply some Loctite, but will check the screws tightness regularly now, and recommend every one does before it locks up at 17mm, a full dismantle will then be necessary, as the screw will not be accessible without a full strip down.
thanks
Mike
Thanks for this how-to. I got mine fixed in an hour. Canon Canada quoted me with $189 CDN for executing the repair.
after fixing the problem, mine doesn’t go to f4 @ 17mm… any idea?
no, no real ideas unfortunately.
just make sure everything is connected correctly when assembled. and those electrical contactors are straight and on the right tracks.
when I did mine first time, it wouldnt focus as I didn’t line that focusing pin.
[...] Otra forma de desmontaje para el mismo proposito. Canon EFS 17-85mm IS stuck/locked zoom repair/disassembly | thydzik's technology blog [...]
Thanks a lot! This happened to me too and your clear guide helped me through it.
Hi!
Zoom stopped working (it was in the position of 17mm, autofocus worked). Did everything as you described. Everything is fine. I found a screw had fallen. Collected back. Zoom works and focus to work longer. All cables are connected properly. Focusing not. Sometimes just focusing occurs in macro mode. Motor hums, but the picture in the viewfinder does not change.
If you have time and opportunity – write to my e-mail (alexay@rambler.ru), in what may be the cause. And how it can be corrected.
Thank. Instruction is very useful.
Alexay,
I had this happen to myself the first time. What has happened is there is a plastic pin about 5mm wide black plastic connected to the focusing ring. You need to make sure this pin is slotted into the correct position. If it is not slotted correctly, it motor and manual focus will work, but it will not focus. Hope this helps.
I have not yet deciphered the lens for the second time. But focus does not work either autofocus or manual focus. Although, perhaps I could never saw this plastic pin. I’ll try to bust again. if I can not find a plastic pin – then will return again.
I have circled the ‘pin’ in this photo, make sure to align it when you put everything back
http://thydzik.com/images/canon-17-85mm-repair-the-final-screws-that-need-tightening-th-pin.jpg
Thank you
Reassemble the lens again, now everything works.
For the first time noticed the plastic pin during assembly.
Thanks for the detailed step by step with pictures. I took the lens apart and now thanks to you it is working fine. I was going to dish out a whole of cash thinking that it was not worth to send it to canon for fixing.
Thank you, thank you and thank you.
Gotta love the web – a million thanks! Your instructions worked great and the photos are key to taking it apart plus putting it back together.
Hi there! Do you know if this fix will sort out an err01 problem (connection between the camera and the lens)? Mayme it is one of the connectors?
Cheers,
Simon
Excellent information, thanks. One small problem – do you know what size screwdrivers I need to do this?
I’d just like to say a massive thankyou for this. I was quoted £100-150 to repair this. Took me two attempts in the end, but I now have a working lens again!
Can I make a suggestion? Can you please modify the article to make that focussing pin issue clearer? If that circled image had been in the main article with a note saying something like “make sure the two silver prongs stradle the black plastic pin” I would have done it in one attempt.
One more point; one of the three black screws on my lens was jammed with metal which meant I couldn’t remove it. If you’re careful though, you can slide that section off wven with one screw still in.
Thanks again!