[forsythem1972]

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Just signed up today to say I've followed these excellent instuctions, and have repaired my K-S2 using a while solenoid purchased as advised. A little scary with the soldering work (I'm not an expert, and aging eyesight doesn't help with this small work!), but all went well and my K-S2 is now working perfectly again! Saved me hundreds of dollars for a professional repair.

Many thanks to Photogem and everybody else who provided extra information - absolutely fantastic!

Michael.

[photogem]

Just signed up today to say I've followed these excellent instuctions, and have repaired my K-S2 using a while solenoid purchased as advised. A little scary with the soldering work (I'm not an expert, and aging eyesight doesn't help with this small work!), but all went well and my K-S2 is now working perfectly again! Saved me hundreds of dollars for a professional repair.

Many thanks to Photogem and everybody else who provided extra information - absolutely fantastic!

Well done Michael!
It proves the old saying: "Once it's shouldered it's light"

[Desperado]

Well done Michael!
It proves the old saying: "Once it's shouldered it's light"

i got mine changed too also,ty photogem..

[Gewitter]

I haven't used my white K-S2 a lot yet, and all pictures were dark after just a but more than 4000 pictures taken.
Now I've successfully replaced the solenoid today, after having purchased a white one from Ebay! (30 € + 9 for postage + 10 for importation fees).
I'm not familiar with soldering, so I spent a ridiculous time checking what type of soldering iron to purchase (I had one but it was old and as cheap as it could be), I finally got one with an adjustable temperature button for less than 20 € which I've used at 300 °C, and soldering wire with a low melting point (indicated as 227℃), if anyone is interested in these details.
By the way I hadn't discharged the flash well enough, and really got a nasty shock when I accidentally touched some of the contacts as I pulled away the front part!
But in the end all worked out well, thanks a lot for the instructions!

[marcusBMG]

Congratulations.

what type of soldering iron to purchase

For this repair, any cheap soldering iron will do, you don't need power. Just make sure it has a good tip: fine pointed, 2mm or so. I haven't tried one of the pocket USB ones but I would think that one of those would work fine for example.

[photogem]

@Gewitter: Well done!

Soldering Iron:

These days due to China flooding the market with ultracheap equipement one can get soldering irons such as this one:
amazon.com: Soldering Iron Kit - Soldering Iron 60 W Adjustable Temperature, Solder Wire, Tweezers, Soldering Iron Stand, Soldering Iron Tips Set, Desoldering Pump, Solder Wick, Heatshrink Tubes ?tag=pentaxforums-20&[110 V, US Plug]: Industrial & Scientific
very cheap.

In Europe I myself would buy an Ersa Multitip, more expensive, no temperature control but very reliable:
Multitip 25W/230V230BD ERSA: Amazon.de: Baumarkt

Of course if soldering is done more regularely one buys a soldering-station, I use an ancient Ersa Analog 80 since decades now and a Weller WSP80 as well.
Not so sure the Weller is really better, the iron itself is lovely small and heats up quicker but aside from that, it is made in China, Weller belongs to the APEX Tool group, irons and tips are all made in China, one can get the WSP80 itself very cheap directly:
Weller WSP80 Soldering iron handle pencil with tip for WSD81 | eBay

Then you add this station:
SOLDERING IRON STATION WELLER Temperature Adjustable *Rapid* Heating Bracket Kit | eBay
and for under $ 100 you have the full 80W Weller for a very cheap price.
In Europe one can find the Weller PU81 station used for sensible money, in USA quite expensive allthough it now is made in Mexico.
In USA the Weller EC2002m used can be found for reasonable prices.

If orig. Weller, then all stations in this turquoise green color will do but temperature adjustment is obligatory.
Any 51-type Weller station with temp.control will do as well.

Tips (they only differ from so called originals that those have the Wellerlogo stamped on their backside):
weller lt | eBay

[m00nr4k3r]

I just registered and account to say big THANK YOU @photogem I followed your guide and my K-S2 is now alive and shoots well exposed. I sourced the solenoid from dead MZ-5n - it's the exact same one with white plastic. Despite being 24 years old, it works well (this MZ-5n was manufactured in '97).

[photogem]

I just registered and account to say big THANK YOU @photogem I followed your guide and my K-S2 is now alive and shoots well exposed. I sourced the solenoid from dead MZ-5n - it's the exact same one with white plastic. Despite being 24 years old, it works well (this MZ-5n was manufactured in '97).

Well done but you have now some risk:
The MZ5n solenoid isn't 100% the same as the DSLR solenoids.
It was designed for 6V and has a slight difference in the size of the coils. It's holding force is different:
A LITTLE BIT OF HISTORY: Development of the solenoid in Pentax cameras - PentaxForums.com

[m00nr4k3r]

I measured the resistance of both: the green one from K-S2 has 29,6 ohm and the white from MZ5n about 30,5 ohm. So about 3% diffrence. They are obviously diffrent even in shape, but to be honest - who cares. It works infinitely times better than the green one (because it works at all ) and photos are exposed as they should be. And that's all I need

[photogem]

I measured the resistance of both: the green one from K-S2 has 29,6 ohm and the white from MZ5n about 30,5 ohm. So about 3% diffrence. They are obviously diffrent even in shape, but to be honest - who cares. It works infinitely times better than the green one (because it works at all ) and photos are exposed as they should be. And that's all I need

The resistance of all of them, China, Japan-made SLR and DSLR solenoids is always around 30ohms +/-5%. Even +/-10% wouldn't really matter.
What matters is holdingforce and size, how it sits.
Here you can see a photo of the SLR solenoid:
https://www.pentaxforums.com/forums/members/85274-photogem/albums/13036-gree...ture123008.jpg
and here one of the DSLR in the same diaphragm-control-unit:
https://www.pentaxforums.com/forums/members/85274-photogem/albums/13035-whit...ture123003.jpg

[m00nr4k3r]

Ok, I see the diffrence now. The question is - do the SLR coil actually fail after some time when used in, say, K-S2?

[photogem]

Ok, I see the diffrence now. The question is - do the SLR coil actually fail after some time when used in, say, K-S2?

The coils themselves never fail. They can only fail due to external damage (touch with soldering-iron-tip or other) or too high voltage (which can happen only in external test-conditions).
Because the holding force is less strong the plunger returns that bit easier with can be sloppy.
That is exactly the same when the plunger is sanded.
So sometimes it has resulted with overexposure and sometimes with wrong exposure.

[m00nr4k3r]

So sometimes it has resulted with overexposure and sometimes with wrong exposure.

Ok, so I'll watch out for that. Since replacement i did few dozen shots and everything look just fine, exposure wise. Thank you for clearing it all out

[Ronald Oakes]

I just replaced mine on my beater Ks2 with a white one from a Ist D I grabbed at a thrift store that had a busted screen .
Now that its over I had a scare on the first frame that was severely overexposed , but perfect since. Im very pleased that its done , and once again my Ks2 functions perfect !
Took about two hours from start to finish and I took my sweet time.
Interesting thing is when ABF happened I sold the camera to another PF member , and then after 2 years bought it back...lol
I have another Ks2 that I have been using that was made in the middle of 2017 that never developed the issue as I read that Pentax did some change to the green solenoid ?
Back when all this started with my very first K30 I wish I knew what I do now. I was unfortunate to have the first one develop ABF while under warranty , sold it after it was repaired only to have it happen to a second like new K30 I bought that was out of warranty. I was so unhappy with Pentax I threw it in the trash can while on a camping trip and vowed never again to buy a Pentax. Nobody knew anything beck then , only that something was wrong as the K30s were dropping like flies with this issue for a while.
At any rate much thanks to Photogem for all the groundwork and tutorials for this to happen. I truly appreciate it !
My Ks2 lives fully functional again !!!!

[ChristianRock]

I just replaced mine on my beater Ks2 with a white one from a Ist D I grabbed at a thrift store that had a busted screen .
Now that its over I had a scare on the first frame that was severely overexposed , but perfect since. Im very pleased that its done , and once again my Ks2 functions perfect !
Took about two hours from start to finish and I took my sweet time.
Interesting thing is when ABF happened I sold the camera to another PF member , and then after 2 years bought it back...lol
I have another Ks2 that I have been using that was made in the middle of 2017 that never developed the issue as I read that Pentax did some change to the green solenoid ?
Back when all this started with my very first K30 I wish I knew what I do now. I was unfortunate to have the first one develop ABF while under warranty , sold it after it was repaired only to have it happen to a second like new K30 I bought that was out of warranty. I was so unhappy with Pentax I threw it in the trash can while on a camping trip and vowed never again to buy a Pentax. Nobody knew anything beck then , only that something was wrong as the K30s were dropping like flies with this issue for a while.
At any rate much thanks to Photogem for all the groundwork and tutorials for this to happen. I truly appreciate it !
My Ks2 lives fully functional again !!!!

If I'm not mistaken, that *ist D has another white solenoid up in the flash. Might come handy since I you have another K-S2.