Nov 01 2011

Why Does Your Canon EFS 17-85mm Lens Flex Cable Going to Err 99?

Published by at 2:37 am under General

Have you found out about the Canon EF-S 17-85mm IS USM lens aperture diaphragm breaking? This is a very useful lens that can be used so many scenarios its hard to be without it! What can be done when it begins to fail?

A new Canon EF-S 17-85mm lens probably lasts in the region of 4-5 years, so you’ll be able to take many thousands photos with it, and will discover it is a great general-purpose zoom lens. Some photographers buy a Canon EF 24-70mm lens to replace it, but keep the 17-85mm for a backup.

Latterly while on a photography road-trip we were using the 17-85mm lens on a Canon 350D camera. Targeting was fine, but any effort to take a photograph would lead to the 350D showing “Err ninety nine” on the LCD, and the camera needed to be turned off and back on to clear the mistake. “Err 99” is a common catch-all inaccuracy code on the 350D, and can imply most anything.

Trying the 17-85mm lens on a Canon 50D led to a categorical inaccuracy : “Err 01 – Communications between the camera and lens is defective. Clean the lens contacts.” Not surprisingly, cleaning the lens contacts with a pencil eraser did not do anything to resolve the inaccuracy.

Some further research on the internet indicated a potential issue with the diaphragm assembly ; the moving parts that set the aperture. Trial – error indicated the diaphragm assembly was failing when the zoom was between 17mm and 24mm and the aperture was smaller compared to f / four. Outside of these parameters, the lens still worked normally.

The “Depth-of-field Preview” button on Canon DSLR cameras stops the lens down to the currently selected aperture. It proved to be a convenient way to check the lens, and it could be confirmed the lens diaphragm assembly was working correctly at the longer zoom range, but failing to operate at all between 17mm and 24mm.

When hitting the DOF Preview button, you should be able to hear the diaphragm assembly working if the aperture is stopped down from the lens ‘ maximum, as well as seeing the lens aperture blades closing when looking into the front of the lens.

Apparently this is a fairly common issue with the 17-85mm lens, typically caused by an open circuit in the ribbon flex wire to the diaphragm assembly in the lens, due to repeated zoom operation of the lens.

Replacement wires are available to repair the Canon EF-S 17-85mm diaphragm flex wire online so you can repair the lens yourself if you have got the time and patience. The 17-85mm lens is out of warranty, and primarily based on a quick search on the web, is worth about $300 if it was totally functional. It is a great lens, and was still gets a lot of use, so it is worth it to get it working again.

You’ll be worried with sending the lens to a repair center, that it’s going to be a pricey exercise and might not be worthwhile given the value of the lens. You may want to considering buying a Canon EF-S 17-85mm lens flex cable online, and attempting the replacement yourself instead . If you are quite good with tools and a soldering iron, fixing a lens might be right up your alley. If the diagnosis of a faulty diaphragm ribbon wire is inaccurate, then replacing the wire won’t accomplish much, apart from learning about how the lens works.

Should it be sent to a repair center, and hope it isn’t going to be too costly to do, or should the owner find a Canon EF-S 17-85mm aperture repair part themselves? Its a difficult question to clear up as it is not an easy operation but if you can do it you’ll save tons of greenbacks in the process.

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