DAL 18-55mm won't auto focus

johngs · 06-27-2015, 01:33 PM

I was using my K-50 yesterday with the DAL WR 18-55mm. It was working fine then for no apparent reason it stopped auto focussing.

When I press the shutter button halfway I can hear a motor whirring, but the lens doesn't move or focus.

I swapped it over for other lenses, including my DA 18-55mm II, and they all worked fine.

Any suggestions please?

robthebloke · 06-27-2015, 01:38 PM

Clean the lens contacts. Switch the camera to manual focus and back again. Then try mounting the lens again

mee · 06-27-2015, 03:52 PM

Does it focus manually still?

johngs · 06-27-2015, 04:11 PM

I cleaned the contacts but that hasn't helped.
Yes it still focuses manually

mee · 06-27-2015, 04:57 PM

Without looking at it.. I really don't know. But it seems like maybe the screw drive 'driver' on the camera might not be reaching the slot on the back of the lens? That is if you can hear a whirring sound.

I'd try turning the lens focus ring slowly back and forth and watch the screw drive 'slot' on the back of the lens to see if it is spinning. It it does, then it is either not catching as mentioned above or there is an issue with communication still. If it is not, then I'd start considering issues of the lens physically.

johngs · 06-27-2015, 09:46 PM

I just cleaned the contacts again.
I see the screw drive slot on the lens is spinning if I manually turn the focus ring.
I tried the lens on another body and same problem happens, so it must definitely be a lens issue, not a body issue I guess.

pishta · 06-30-2015, 12:55 PM

The screw drive may be stripped in the lens. Use a small screwdriver on the lens focus drive pinion and turn it while holding the focus ring steady. If it fights you, its still engaging. If it turns without forcing the lens to turn, you are stripped. It may have sheared the drive shaft or simply broke a plastic drive gear.

johngs · 07-02-2015, 04:35 PM

Thanks Pishta .. I just tried your suggestion and the focus ring still tried to turn while I held it and turned the drive pinion. So I guess that means its not stripped or broken any gears.

I took the lens to the store where I bought it. They said its out of warranty and not worth paying to get it fixed. They told me the name of a lens repair shop but said it would cost more than the lens is worth to have to looked it.

stevebrot · 07-02-2015, 05:22 PM

Originally posted by johngs

I took the lens to the store where I bought it. They said its out of warranty and not worth paying to get it fixed. They told me the name of a lens repair shop but said it would cost more than the lens is worth to have to looked it.

That is good advice. You should be able to get a DA 18-55/3.5-5.6 with metal base (non-DAL) used for less than $100 USD.

Steve

06-27-2015, 01:33 PM	#1
johngs Senior Member Join Date: Dec 2008 Location: Christchurch, New Zealand Posts: 229	DAL 18-55mm won't auto focus I was using my K-50 yesterday with the DAL WR 18-55mm. It was working fine then for no apparent reason it stopped auto focussing. When I press the shutter button halfway I can hear a motor whirring, but the lens doesn't move or focus. I swapped it over for other lenses, including my DA 18-55mm II, and they all worked fine. Any suggestions please?

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06-27-2015, 01:38 PM	#2
robthebloke Veteran Member Join Date: Sep 2013 Location: Sydney Photos: Albums Posts: 844	Clean the lens contacts. Switch the camera to manual focus and back again. Then try mounting the lens again

06-27-2015, 03:52 PM	#3
mee Veteran Member Join Date: May 2010 Posts: 7,403	Does it focus manually still?

06-27-2015, 04:11 PM	#4
johngs Senior Member Join Date: Dec 2008 Location: Christchurch, New Zealand Posts: 229 Original Poster	I cleaned the contacts but that hasn't helped. Yes it still focuses manually

06-27-2015, 04:57 PM	#5
mee Veteran Member Join Date: May 2010 Posts: 7,403	Without looking at it.. I really don't know. But it seems like maybe the screw drive 'driver' on the camera might not be reaching the slot on the back of the lens? That is if you can hear a whirring sound. I'd try turning the lens focus ring slowly back and forth and watch the screw drive 'slot' on the back of the lens to see if it is spinning. It it does, then it is either not catching as mentioned above or there is an issue with communication still. If it is not, then I'd start considering issues of the lens physically.

06-27-2015, 09:46 PM	#6
johngs Senior Member Join Date: Dec 2008 Location: Christchurch, New Zealand Posts: 229 Original Poster	I just cleaned the contacts again. I see the screw drive slot on the lens is spinning if I manually turn the focus ring. I tried the lens on another body and same problem happens, so it must definitely be a lens issue, not a body issue I guess.

06-30-2015, 12:55 PM	#7
pishta Forum Member Join Date: May 2015 Posts: 92	The screw drive may be stripped in the lens. Use a small screwdriver on the lens focus drive pinion and turn it while holding the focus ring steady. If it fights you, its still engaging. If it turns without forcing the lens to turn, you are stripped. It may have sheared the drive shaft or simply broke a plastic drive gear.

07-02-2015, 04:35 PM	#8
johngs Senior Member Join Date: Dec 2008 Location: Christchurch, New Zealand Posts: 229 Original Poster	Thanks Pishta .. I just tried your suggestion and the focus ring still tried to turn while I held it and turned the drive pinion. So I guess that means its not stripped or broken any gears. I took the lens to the store where I bought it. They said its out of warranty and not worth paying to get it fixed. They told me the name of a lens repair shop but said it would cost more than the lens is worth to have to looked it.

07-02-2015, 05:22 PM	#9
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by johngs I took the lens to the store where I bought it. They said its out of warranty and not worth paying to get it fixed. They told me the name of a lens repair shop but said it would cost more than the lens is worth to have to looked it. That is good advice. You should be able to get a DA 18-55/3.5-5.6 with metal base (non-DAL) used for less than $100 USD. Steve