The first disassembling of an unknown lens normally takes a lot of time for me – and sometimes I make unnecessary steps.
If You want only to change the aperture module, or only the aperture flat cable, You can do it in the following way (the first steps are not on the pictures, so the USM module and the electronic board are already dismantled.)
If You want to clean the internal side of the lens, You have to disassemle the lens completely, of course.
These are the 3 guiding rollers (in fact, there are 3 x 3 rollers, positioned at 120 degrees).
No. 1. is for the last lens group,
No. 2. is for the IS module moving lens,
No. 3. is for the aperture module.
At first, You have to get out the No. 1. and 2. (3 + 3 rollers and 3 + 3 screws). At the first time is not very easy, because they sit very tight in their place. You can help this with a small flat screwdriver, or with a big wood-screw, using it like a cork-screw. The best is, if You make a small tool for this operation, like this:
See here: https://canonrepair.wordpress.com/2013/03/16/lens-disassembling-tools-roller-extractor-clamp/
The rollers are apperently the same size, but is good to keep them separately for each group.
Now You can pull out the last lens TOGETHER with the IS module (because the IS is in the inside of the lens module).
Don’t forget , You will have to put it back in this position. It’s easy because the two flat cables give you only one possibility.
The next step: to take out the 3 rollers No. 3 (for the aperture module.)
You may take out the screw for the flat cable only now.
After that, you can pull out the aperture module, with the cable, and the long black metallic guide.
Be careful, the new aperture comes without the metallic guide, so you have to use the original!
Assembling in reversed order 🙂
For greasing the guides, rollers I used a PTFE + silicone oil based grease – (in fact a grease for Volvo cars), but be carefull, only the really needed amunt, otherwise You will have grease on the lens.
By the last lens which I’ve repaired I tried to change only the cable. The operation was successfull, soldering OK – but the lens was not working. No contact problems, and nothing wrong measurable.
After complete change of the aperture, was good.
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Hi cannon Repair, I wass try fix two lens with flex apeture cable broken, but apfter reassembly, an test to the camera, error 01 was appear. really apreciate if you can share your experience about this issue. than kyou….
there can be a few possibilities:
– aperture module died during soldering (after soldering the minimum check is to measure the resistance of the 2 coils, approx 20 ohm. unfortunatelly the position sensor (4 pins) cannot be measured with simple method.
– cable is of bad quality
– contact problem in the PCB connector
Thank you for your response, will check closely as per you suggestion. thank you….
good guide. I got the cable from ebay. Anyone attempting the soldering of the cable take extreem care. The plastic melts really easiely and teh pins pull out!
for desoldering I ALWAYS use desoldering litze, a special copper wire which absorbs the tin.
Where did you purchase the whole aperture module? I can only find the aperture flex cable for sale. I would like to avoid having to solder a new cable.
http://www.ebay.com/itm/CANON-17-85MM-4-5-6-USM-POWER-APERTURE-DIAPHRAGM-UNIT-PART-NEW-GENUINE-OEM-/390482750985?pt=Digital_Camera_Accessories&hash=item5aea95ee09
here is the answer. This is one of the most seroius ebay sellers. A little bit expensive, but correct.
solderind the new cable is not a problem. DESOLDERING of the old one is more difficult. Use a desoldering litze (a very thin special copper wire )
Thank you, much aappreciated
My 24-105 got the err 01 problem yesterday. Very sad!
Yes, it’s bad to have no lens for a while.
But the best way to make knowledge with the inside of this beautiful lens :)))
I would say I could repair it for You, but it’s not to easy because the distance.
But if You need help in repairing, drop me a mail
János