Dual Shock (1) Cleaning and Repair

Starting with a Dual Shock controller of unknown origin (I think it was bundled with one of the many used Playstations I've bought in my lifetime) and unknown function.

 

 

Before

Not even hiding in their little recesses were the screw heads safe from the crud.

The screw heads encrusted with who knows what.

Sweat, food, mold, dandruff.  Sure loves to hide in the cracks.

Mmm pet hair.

Even more pet hair, yay.

No recess is safe

Ever wonder what gets up under the D-pad?  Well wonder no more.

After

After several passes through the ultrasonic cleaner, and some judicious application of compressed air, things are looking pretty clean.

Most of the discoloration is gone from these screws, though I believe what remains is likely corrosion that can't be cleaned off without abrasion.

The ultrasonic nailed every nook and cranny

I used to spend a lot of time with toothbrushes trying to get at spots like this. Well no longer thanks to the power of sound.

No crud was safe from the vibrational goodness.

I've never been able to get buttons quite this clean.  Maybe 95%.  Really really liking the ultrasonic.

Renewing the Thumb Caps

Ever since running into a Dual Shock 2 controller with a sticky cap, I've been experimenting with a new method of re-naturing the covering.  I don't do any scrubbing or wiping at all, simply allow the cap to soak in 3-in-one silicone for a good hour then dry completely.  There may be long term side-effects that I'm unaware of, but so far it's been 100% successful in bringing back the supple and clean feel of the caps as they originally were.

It may be hard to make out, but the thumb cap is immersed all the way to the underside of the "hood".

Just after removal from its silicone bath

The one on the right has been drying for about an hour, the one on the left just came out.  After another hour or two they'll look feel and perform almost like new without scrubbing or removing material.

Refurbishing The Control Sticks

As I said when I started, I didn't know whether this controller was actually working properly before I started, but I decided it would be a good chance to get some images of what it looks like to tear the thumb stick down and refurbish it.  The design hasn't changed much between the original Dual Shock and the Dual Sense 4 - I've used essentially the exact same technique to fix the sticks on a PS4 controller.

First order of business is to de-solder the thumbstick module.  It's fairly easy to do considering this is a 1-layer PCB without any through-hole-plating.  The only annoying part is using precision pliers to straighten out the mounting pins that they twist to hold the sticks in place before soldering.

To remove the potentiometers, use a precision screwdriver and push in while levering outward.

Once you've worked the tension clip free, repeat on the other side.

Here's what the module looks like with the vertical potentiometer removed from the module.  This is also a good reference for the correct orientation of the white conductor disc for when you re-assemble.

For the sake of completeness here's the horizontal potentiometer removed.  Note the shaft is very different from the vertical one.  I believe the potentiometers are identical, but I never remove more than one at a time to ensure they all get put back in their original places.

To remove the white conductor disc, use tweezers to gently press the tension clips together. Pretty much no force is needed.

Here's a microscope shot of the disassembled potentiometer.  The potentiometer transmits position by the changing resistance along the rings inside the green housing.  On the left, circled in red are the contact points on the conductor disc.  On the right boxed in red are the wear spots where the conductor disc contacts the ring.  To clean and freshen this potentiometer up, I used a fibreglass pen to clean away the oxidation from both the contact points on the conductor disc and the contact rings in the green housing.  Before re-assembly I applied a couple drops of Deoxit5 to coat and protect the surfaces from future oxidation.

Fixing A Corroded Trace

While I had the controller apart, I noticed a raised spot on the surface of the PCB but I did not investigate it like I should.  If I had, it might have saved me some time.  Somehow one of the test points used by the factory to validate the PCB  was completely corroded.  The copper oxide formed a mound over top of it that looked like a dab of glue or something.  For some reason I mentally dismissed it until after I assembled the controller and discovered that the start button did not work.  The corrosion had actually eaten away the trace connecting the start button to the microcontroller chip inside the Dual Shock.

A mound of corrosion - this should not be there!  Not sure how this one test point was the only one affected, but it was.

I wasn't sure at first whether the trace had been severed until I scraped away the solder mask with a craft blade and fiberglass pen.  There is an obvious dark line around the left edge of the test point where the trace has been eaten away by the corrosion.  I scraped the solder mask off of the via where the trace goes so my multimeter could confirm continuity (or lack thereof)

The repair was simple enough - scrape away the solder mask to expose the trace, then coax a tiny amount of solder to bridge the gap.  Flux was used to make the solder a little more cooperative.  From there, I tested continuity from the upper pad of the start button contact and the exposed via and confirmed it was re-connected.

Full controller function was easily confirmed with this tool.

After

And here we have it.  So clean it practically looks brand new.  The original thumb pads are looking particularly good.  Everything works smoothly, including the refurbished sticks and repaired start button.  Ready for several more decades of worry-free service.