Solenoid-Replacement Pentax K-S2
(Pentax K-70 is almost identical except screw of solenoid situated on left instead of right side!)

Tools required:
- Soldering iron with pencil-tip: Ersa Multi-Pro 20W or soldering needle/USB soldering iron. I use the Weller WS81® soldering-station.
... (Butan-gas soldering-iron = An absolute No-Go! Too hot, it will do damage!)
- Solder: Good quality thin resin flux solder (I use 0,75mm S-SN60PH40 leaded-solder which melts already at 190° C:
... For such short and small work it is not really dangerous because it contains some lead.
... You can also use rosin-/fluxfree solder and add colophonium later on, my personal prefered method.
- 1 x Screwdriver JIS 000 or JIS 00 (you can also use a PH00 + PH000 but JIS is better, Pentax screws are JIS!)
- 1x tiny Screwdriver flathead like 1.8mm (for lifting the rubber-grips held by double-sided-tape)
... The Vessel 9902 set is ideal, the long JIS screwdriver is perfect for reaching the screw of the solenoid!
- 1x Tweezers or precision pliers
- Headlamp is very useful, makes things easier
- Photos of the K-S2 with location of screws
- And of course the correct solenoid, i.e. the (white) Japan-DSLR-Version ONLY! Why only this one you can study HERE
(and we don't discuss other solenoids in this tutorial as this not for cheapskates but the only proper solution!)

Preparation:
- Print out all those photos, glue them on some cardboard, drill 2mm holes where the screws are located so you can later on stick all those screws into those holes. Makes it easier and safe due to different length of the screws.
- Make sure you took the battery out 24 hours prior undertaking the repair. This is for discharging the flash-condenser, which is well protected within the K-S2, nevertheless you don't want to risk getting a nasty shock! This condenser charges as soon as you open the pop-up-flash with battery inside the switched-on camera! So don't open the flash prior removal of the battery! You need to open it for access of 3 screws!
- For a better option how to discharge the flash-condenser read HERE

Sequence of opening the body (Body-cap is mounted on the K-mount for protection of sensor etc.)

1. Remove all screws from the bottom part:
- 11 x screws direct access (green arrows)
- 3 x behind the battery-door (blue arrows)

- Like with other Pentax DSLR, there is one screw deep within battery-case left side: DON'T take this one out!



2. Remove all 3 x screws from the left side: 2 of them hidden behind the rubber grip
The rubber grip is fixed w. doublesided adhesive tape, just use a tiny flathead screwdriver to get inbetween the body and the rubber and lift it!






3. Remove all 3 x screws from the right side all 3 hidden behind the rubber grip (which you lift partly only ):






4. Open the flash (battery is out!):
Remove the 2 x screws there underneath the pop-up-flash and the 2 x screws where next to where you fix the strap/belt:






5. Remove the 2 x screws behind the rubber-eye-cup (which you slide upwards to remove it):





6. Now you lift the TOP-PART 1 cm (with the open flash). This is very important because otherwise the front-part is more difficult to remove!



7. Set the AF-MF switch on MF (see photo #2 where it is yet on AF)! Check position again when you assemble it back!
Make sure you understand its position: When on AF, the screwdrive is out, when on MF, it is retreated inside this small hole of the stainless-steel bayonet!
Take the FRONT-PART OFF: It is a bit tight, you might have to lever a bit to release it but don't worry, this is normal!



8. Now you have access to the green solenoid:





9. Unsolder both leads and unscrew the screw on the right side (K-70 left side, only difference). Take the solenoid out.


10. Install the white-Japan-made Solenoid (the only correct solution, avoid filing/grinding/sanding!):





11. Make sure you tighten the screw, you might want to fix it with threat-locking-laquer or nail-varnish, but I never needed to do it!

12.Solder the two wires back to the pins (left=pink//right=lilac). Crucial to do a good job, hold the wires with tweezers and pull to make sure they really are well soldered!

13. Now bring the top-part (with flash) back into position for being able to test the solenoid.
You might want to fix it with 2 screws (right to the viewfinder and the on the right strapholder, so the buttons have a good contact!
CLOSE THE POP-UP-FLASH!
Insert the battery and plug on a lens.
Switch the camera ON, in Av-Mode wide open take a photo.
You can see if the solenoid actuates and the photo should be alright.
If all is alright, take the lens, battery and the 2 screws off again.

14. Lift the Top part again slightly

15. AF-MF-Switch alignement: The is crucial now:
- Outer part of AF-MF-switch on the front-housing on MF:


the same switch from the inner side of the housing, you can see the rod which needs to be aligned:




- The internal part (black plastic, white arrow left) has to be upwards...


.... so the screwdrive mechanism "retreats" into this tiny hole (white arrow left). This mentioned rod of the AF-MF switch connects with the internal part!
(you have checked this before and understood the principle well, remember!)

16. Assemble to front-part back on and then the top-part (w. flash)

17: Test AF-MF-Switch! If it doesn't work correctly, take the front-part off again and realign!

18. There is this small plastic ring on the microphone-socket, don't lose it:


When you come to the bottom-plate, make sure you haven't missed this small part, which sometimes comes off:


It slides just on and off easely and is there to protect the cables from the display:


On its place it looks like this:


and with the bottomplate back on place it looks like this:


19. Very early K-S2's had a copper-washer glued with the same red thread-locking-laquer as the solenoidscrew onto the bottom part. You can see it very clearly here on this white K-S2:

This washer was used to even out a tiny hight-difference which was solved more elegant in later versions of the K-S2 and the K-70 (same body):

20. The rest is clear now, all screws in the same order as you got them out.


21. Test the K-S2 again: All should be fine

I have not written here about the differences of the solenoids, you can read more about this important issue HERE

Good luck!


If you are interested in this very interesting history of the development of the solenoid in Pentax SLR and DSLR bodies, then read this post:
A little history about the development of solenoids in Pentax cameras

[Loyalbutwhy]

My first ever camera repair - rather testing for me and took a while, but it seems to have worked. Some feedback FYI.
1) My heartfelt thanks to Photogem for the detailed guidance on this repair.
2) Pay attention to Photgem's advice re saving screws and correctly identifying them. My system fell apart quickly and screws thereafter were identified by length (used a cheap plastic gauge with vernier.) But the screws have different threads as well as lengths, so I wasted a lot of time checking and choosing screws at re-assembly stage.
3) Photogem doesn't say so, but the rubber handgrips have to be peeled off to get at some of the screws. This feels a bit scary but the rubber is thin and folds and its adhesive re-attaches okay. I used a jewellers screwdriver start the lifting.
4) It is not mentioned, but to get at the screws under the viewfinder eyepiece, the eyepiece assembly has to be slid off upwards.
5) In step 16, image 3, its says "The internal part (black plastic, white arrow left) has to be upwards...". But since the image shows the camera upside down, the part has to be moved downward, toward the bottom of the image.
6) In my case, when I was positioning the new solenoid unit in place, the unit separated into two parts, namely the solenoid and the U shaped part that moves within it. I put it together again and positioned and soldered the unit in place as per instructions. But then on the old unit I saw the internal metal part has a dimple on one side, indicating that it is not symmetrical, i.e should go in one way and not 180 degrees from that. I don't know which way I put mine in. Does this matter? Anyway, I took a punt on reassembling as is and find the camera appears to be working ok.
7) My PH screwdriver was a multi-bit Picquic Teeny Turner, which is short and not suitable for dealing with the solenoid screw, which is hard to get at anyhow. For this and some of the other screws I found that a flat blade jewellers screwdriver set was very useful, albeit recognising the potential for damaging the screws. I could not source JIS screwdrivers locally.
8) At one point, a screw flicked from my fingers - not an uncommon event - but then disappeared - I gave up after more than an hour carefully searching bench and turning over everything in nearby areas. Depressing. But then, next day, to my relief, there it was - sneakily attached to and hidden by the magnetic shaft of the Teeny Turner.
Overall, a very satisfactory exercise, possible only because of Pentax Forums and Photogem advice - thanks!

[photogem]

Well done and particular if it is a first repair!


I remember you had asked about how to lift the rubber-grip in the other tutorial thread.


Somehow I thought that when I write "3 screws hidden behind the rubber-grip" it is logical that one has to lift the rubber but yes, my logic based on many other repairs does not go sychronious to the logic of others and so such a question can arise.
The same goes for the rubber eyepiece (eyecup): When I write 2 screws behind the rubber eyecup I thought it would be evident to every Pentaxuser that you can slide it up (because one cleans it, replaces it, changes it against the O-ME53 etc)

So I altered the tutorial accordingly to make it easier.

Very well observed that the inner part of the M-AF-switch on the photo was kind of upside down!
I had a different photo there but this one (which actually is from the K70 tutorial) showed more details so I took it without realising that "upwards" could really be misleading. Just had to "turn" the photo 180 degrees

[lohr500]

A massive thank you to photogem for putting together such a great step by step guide.

My KS2 failed yesterday with the dreaded aperture solenoid problem.
I hadn't used it for over a year and took it with me to use at our daughter's university graduation ceremony. (Subsequently learned that the problem seems to be made worse by lack of use!).
Fortunately we all had half decent mobile phones so could capture the happy events of the day on those.

I contacted Ricoh expressing my dismay that an expensive Pentax camera with very light use had failed with a well documented fault and asked if they would be prepared to help with repair costs. As expected, the reply was an unhelpful no, leaving me with the feeling that I would never waste my money on another Ricoh Group product ever again.

So before doing enough research I ordered a replacement green solenoid from a Hong Kong based seller on eBay. This I now realise from photogem's detailed explanation of the different solenoid types was a mistake. I have put in a request to cancel that order and await a reply. I then found a UK seller who was offering a genuine white type solenoid which I have purchased.

Today I dismantled the KS2 using photogem's instructions and I now await delivery of the replacement solenoid. Without the guide I am sure that I would not have been able to locate all the casing screws and would probably have damaged the camera trying to take it apart.

The detail in the guide is amazing, including explaining where the two washers go that I found on the desk after pulling the camera apart. ( One on the mic socket and the other which acts as a spacer on the base plate. ) Without that detail I would never have figured out where those two washers had come from

So once again, thanks for documenting the process so clearly.

Looking forward to receiving the replacement solenoid and getting the KS2 working again.

[photogem]

@lohr500: Thanks for your kind words. Let us know again when you have installed the new solenoid how it went, but I'm sure now all will be fine.
Just don't forget to do the alignment of the AF/M-switch, this is crucial and might need 2 or 3 attempts until perfect, somehow with the K-S1/2 and K70 this is a but more difficult although the K30/50 has three instead of just 2 positions.

[lohr500]

I will report back on progress once the replacement solenoid arrives.

One question, do you find it easier to attach the new solenoid first and then solder on the wires, or to solder the wires before attaching the solenoid?

[photogem]

One question, do you find it easier to attach the new solenoid first and then solder on the wires, or to solder the wires before attaching the solenoid?

I do it as explained in the tutorial: First I attach the solenoid then solder the two wires.

The reason is, that the wires are very short and you would need something to hold the solenoid close by.

Of course if you have a third person knowing exactly what to do, you could hold the solenoid and the wire and then the 3.rd person does the soldering but

there is little space so this would require a "good team" having good experience in doing so.

[lohr500]

Replacement white solenoid arrived today and I was able to cancel the eBay order for the green solenoid.

It was easy to tell just by carefully pulling out the plunger that the holding force on the white solenoid was much less than the green one I removed from the camera.

A couple of comments to add to photogems brilliant guide which may be helpful :

Firstly I inserted a small piece of cardboard in the camera before attempting to attach the solenoid screw and do the soldering. I thought if I dropped the screw the cardboard might catch it and prevent it falling into the inner most depths of the camera. Also the cardboard would catch any drips of solder if I was clumsy with my soldering. As it turned out there was no need for the cardboard but better safe than sorry.

Secondly when refitting the base, make sure the retaining tag for the pull out rubber blanking piece (which I presume is there to help remove a stuck battery) goes between the battery housing and the outer case. When I fitted the base initially, I hadn't noticed that the tag was inside the battery compartment so it wasn't captive and was preventing the battery from being inserted smoothly.

I am pleased to report that the KS2 is now back in working order and as good as new

Once again, a big thank you to photogem for the guide.

ps. Sorry about the poor photo quality. Best I could do with my cheap compact camera.

[photogem]

I am pleased to report that the KS2 is now back in working order and as good as new

Well done, congratulations!

.... when refitting the base, make sure the retaining tag for the pull out rubber blanking piece (which I presume is there to help remove a stuck battery) goes between the battery housing and the outer case. When I fitted the base initially, I hadn't noticed that the tag was inside the battery compartment so it wasn't captive and was preventing the battery from being inserted smoothly.

This rubber piece is there for either the K-AC128 AC Adapter or the K-AC109 AC Adapter (aftermarket)
There is this part looking like the D-LI109 but with a cable to fit into the battery-box. Without this removable rubberpiece this cable would jam!

As for the solenoid-screw: As the tip of my Vessel 9900 JCIS-0 screwdriver always is magnetised (and remagnetised when it weakens) I just "hold this tiny screw" with the tip and can put it such right into the hole of the solenoid to fix it. But... I am used to it!