[WorksAsIntended]

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Is there an overview when (build date and serial number) Pentax changed the sdm generation at which lens series?
The failures are a series issue. I usually expect my lenses to outlive multiple body generatios. Has the newer generation significant less problems or just a little?
I am sorry to hear about your lenses!

[RayeR]

Hi, in my SMC DA 17-70/4,0 AL (IF) SDM the SDM motor finally failed too. It's dead that I cannot hear any typical high-frequency noise. I will ask for a repair but I'm also thinking about a mechanical mod to add some spindle to transfer AF movement from the body. So for this case it would be usefull to disable SDM control in EEPROM.
As I tried the steps described on 1st page on my K-3 body it doesn't work.
I can go to debug menu and select save lens to SD but it does nothing - no message, any file was created.
When I select test of body - lens communication the LCD screen goes black and camera hangs. So it seems this feature was removed from K-3 FW. I use FW version 1.30 would it work with older version? I can also use my old K-30 partially damaged body with mirror problem but for lens EEPROM reading it should be usable. Is it known to work on K-30 and if yes what FW version?

[UncleVanya]

Hi, in my SMC DA 17-70/4,0 AL (IF) SDM the SDM motor finally failed too. It's dead that I cannot hear any typical high-frequency noise. I will ask for a repair but I'm also thinking about a mechanical mod to add some spindle to transfer AF movement from the body. So for this case it would be usefull to disable SDM control in EEPROM.
As I tried the steps described on 1st page on my K-3 body it doesn't work.
I can go to debug menu and select save lens to SD but it does nothing - no message, any file was created.
When I select test of body - lens communication the LCD screen goes black and camera hangs. So it seems this feature was removed from K-3 FW. I use FW version 1.30 would it work with older version? I can also use my old K-30 partially damaged body with mirror problem but for lens EEPROM reading it should be usable. Is it known to work on K-30 and if yes what FW version?

Nope, neither the k-1 nor k-3 will work. Also the lenses that do work are all lenses with integrated screw drive. I'm unsure that there is any reasonable way to add screw drive to the 17-70.

Having shot the 17-70 I can see why you might want to fix it. Honestly however you are better off getting a replacement, replacing the motor yourself, or buying another lens like a 16-85.

[RayeR]

Nope, neither the k-1 nor k-3 will work. Also the lenses that do work are all lenses with integrated screw drive. I'm unsure that there is any reasonable way to add screw drive to the 17-70.

OK, and with K-30 would it work? Or is there some body + FW list that was approved to work for this mod?

Having shot the 17-70 I can see why you might want to fix it. Honestly however you are better off getting a replacement, replacing the motor yourself, or buying another lens like a 16-85.

I'd like to replace the SDM myself but I cannot find any replacement SDM seller (ebay, aliexpres, alibaba etc...). Neither nobody was offered me a damaged lens that I advertised for in my country.
I already disassembled the lens and SDM replacement is easy task. I found a problem why SDM went completly silent in my case. There was a small blown resistor in 0603 package beside a small chip in SOT23-5 package that I didn't identified but it might be a motor driver. The resistor is connected between pin 4 of the chip and Vcc. Unfortunately as resistor was blown I cannot read it's value. I can only estimate that it was 0R or some low-ohm value and could work as a fuse. This component costs a few cents but I belive that some servis center would replace and account a price of whole PCB. So I replaced it with 0R and the SDM is squeking again but it doesn't move, turning the SDM screw doesn't have any effes, except if turned wrong then SDM axle jams and don't move even by hand (some force needed). So I think it's definitely dead and I need new SDM for replacement.

[UncleVanya]

Sorry. Typo on my part. No. The k-3 and k-30 are known to not work. It is easy to convert with a k100d or k100d super. Many other bodies work.

[felixkh]

Sorry. Typo on my part. No. The k-3 and k-30 are known to not work. It is easy to convert with a k100d or k100d super. Many other bodies work.

Even the K10D and K20D can work

[UncleVanya]

Even the K10D and K20D can work

The k10d only works with the older firmware unless pktether works with the newer firmware. The k-5 works with the right setup as well.

[Mistral75]

The K10D works with firmware 1.00-1.30, not with 1.31 (the latest one).

[RayeR]

OK, thanks for info. I don't own such body neither know anybody else who have it. If the chip is standard serial I2C EEPROM it could be read/written by some cheap serial programmer.

I'd would rather like to replace the SDM but I cannot find any seller of spare part. I spent some hour searching through ebay. There is a lot of replacement parts for camera bodies (covers, LCD, PCB, chassis, CCD, flashes...) but nothing for pentax lenses. Strange, when I searched for Nikon lens parts there are plenty of SWM motors available. E.g. this one looks similar to pentax SDM but seems to be bigger / higher. Also for nikon lenses is easy to find a service manual but nothing for pentax SDM lens. I also tried to ask some ebay sellers with rich spare parts portfolio if they could offer SDM for pentax. A half of them replied and told that no.
There's also video

You Tube

You Tube

of SDM replacement. I sent him an email but no reply.
So is it really impossible to buy a Pentax SDM spare part?

[builttospill]

OK, thanks for info. I don't own such body neither know anybody else who have it. If the chip is standard serial I2C EEPROM it could be read/written by some cheap serial programmer.

Uncle mentioned this, but I wanted to repeat it so you're not looking for a camera body to edit lens data: the 17-70 does not have a screw-driven focus shaft. There is no way to use a camera body to convert it to screw drive from SDM because it doesn't have the required secondary system. It's SDM (or manual-focus) only.

[david94903]

Even the K10D and K20D can work

I used my K20d, with no issues, when converting my DA16-50mm to screw drive. Wonder if I should list that ability as a "feature" when I list it on the Marketplace?

[UncleVanya]

OK, thanks for info. I don't own such body neither know anybody else who have it. If the chip is standard serial I2C EEPROM it could be read/written by some cheap serial programmer.

I'd would rather like to replace the SDM but I cannot find any seller of spare part. I spent some hour searching through ebay. There is a lot of replacement parts for camera bodies (covers, LCD, PCB, chassis, CCD, flashes...) but nothing for pentax lenses. Strange, when I searched for Nikon lens parts there are plenty of SWM motors available. E.g. this one looks similar to pentax SDM but seems to be bigger / higher. Also for nikon lenses is easy to find a service manual but nothing for pentax SDM lens. I also tried to ask some ebay sellers with rich spare parts portfolio if they could offer SDM for pentax. A half of them replied and told that no.
There's also video YT video of SDM replacement. I sent him an email but no reply.
So is it really impossible to buy a Pentax SDM spare part?

For a brief time keh offered and replacements at good prices.

Honestly somewhere the info must exist and the part is likely generic enough.

---------- Post added 01-03-19 at 12:40 AM ----------

KEH SDM Repair - PentaxForums.com

[RayeR]

>builttospill
Sure I know that 17-70 SDM doesn't have screw drive axle but I'm thinking about a mechanical mod that it could be. And if I would be able to make it then I will also need to reprogram EEPROM to disable SDM. When I played with lens one time it accidentally happened that the K-3 body started to run screwdriver, maybe there is some fallback in fimrware. So it is 100% possible to make screwdriver running for a lens without screw AF. But I was unable to repeat this occurence.

>UncleVanya
I asked KEH sevice but they kindly replied that they don't sell spare parts. And sending to USA will add extra cost...
I also got reply from DIGI SERVICE (Bulgaria) and they offerend SDM alone for 135 euro + shipping. He also told me that it would be necessary to adjust something in EEPROM for new SDM. This seems to me quite high price for a part a the whole lenses (used) are avail. on ebay for cca 200 euro. I probably try a luck with nikon SDM as its ultra cheap compared to pentax one and I have nothing to loose...

[builttospill]

I probably try a luck with nikon SDM as its ultra cheap compared to pentax one and I have nothing to loose...

If you go this route please document your process with photos and step-by-step instructions for a new thread here on the Forums. I think many would be interested in seeing how this turns out.

[madmax]

Hi, check youtube there is a guy that dissassambles the sdm drive motor. That may be helpfull. I watched it and It seemed to be too complicated to pay off for a longer usage after repair.
Madmax