Dualsense BDM-010 X button issue

[mortal91]

Hi guys!

My Dualsense controller X button will not work unless I press X and Touchpad button at the same time, or when I hold down the touchpad, then it always works. Sometimes the triangle button doesn't work either.

Any ideas what might be causing the problem? What could I try?

Thanks in advance!

[RDC]

Have you done anything to the controller?

[mortal91]

Nope, it's fully original. I did nothing to it. I changed nothing. It's really strange.
I did reset already the controller but it doesn't helped and it has also the newest software.

Does anyone have an schematic maybe?

[RDC]

Since the X works when the TP is pressed in, leads me to think something just isn't making good contact in there. I'd tear it down and clean all of the contacts good first, possibly something has gotten in there on the connection between the Motherboard and the Flex board with the X button contacts.

All of the Digital buttons are active Lo and go straight to the MCU, except for L3/R3 which are active Hi, so if it's not a funky connection between the Motherboard and Flex it could be a touchy solder joint on the MCU. The board is 6 layers, so not really fun to trace out.

[mortal91]

I cleaned the flexboard already, it doesn't worked out.
You mean, I should reflow the MCU (SIE CXD90064GG)? Or maybe I could keep that chip pressed, and see if the X button works?

[RDC]

Pressing on the MCU will also press on the Flex to Motherboard connection, so if that worked the issue could still be that connection. Could be the PCB has an issue and a via or the X trace is cracked, then reflowing the MCU might make that better or worse, intermittent issues can be all kinds of fun to figure out.

You can take just the motherboard and ground the X line with a jumper wire to see if X works before trying to reflow or pressing and really changing anything. If X works that way, then the Flex or that connection most likely has the issue, but it could still be that wen the PCB is in place it's getting tweaked and opening up that X line. That kind of problem can give you a real fit before you figure it out.

[mortal91]

Today I tried a new conductive film, which works, but it didn't solve the problem. So it must be something else.

So you mean, I should just ground X with a jumper wire like this? And so should X button work?

[RDC]

You will need to remove the solder mask form the via there first, but yes, doing that is the same as pressing the X button.

[mortal91]

Okay, thank you. I'll do it on friday and let you know if the X button works.

[mortal91]

So I did it, and it works that way. What now? What do you think I should do next?

As I wrote, I have already replaced the conductive film with one that works in another controller, but that did not solve the problem.

Thanks in advance for your advice!

[RDC]

All that's left is the connection on the other side of the board where it mates to the Flex. It could be that X contact has a higher resistance than the rest, or that one didn't form right, there's no pic of the other side there to see if anything there looks wonky. One trick you might try, that has also worked on the DS4 controllers as they have the same setup, is there is a small piece of foam under the Flex contacts where it mates to the board. That's there to keep a little bit of pressure on those contacts. You can 'shim' that with a piece of paper underneath it, so the foam then puts a little more pressure on the contacts when it's all put back together. Might work, might not, but you're now getting int the territory of everything is checking out good, but it's not working, and without that kind of problem in hand it's a bit harder to tell what might be causing it without being able to poke and prod to see how it acts.

[mortal91]

You won't believe it... Now that you mentioned the foam under the flex contacts, I checked and it was slipped. I adjusted it and it works now perfectly. So thank you very much for your help!

I have an another controller where the touchpad does not work. I have tried several, so the problem is definitely with/on the board. Do you have any idea?
Should I open an another topic or can we discuss it here?

[RDC]

Welcome.

There are a couple different versions of the Touchpad board for the BDM-010, and I'm not sure if they are interchangeable or not, never tried a swap,so it might need to be the same type as the original one that was in it.

Pretty much all of the TP connections are either power, ground or go directly to the MCU thru a handful of Resistors. A couple of the lines have Pull-Up Resistors on them. Haven't seen enough of them with issues to really even have a best guess there aside from the kind of obvious things like making sure the ends of the FPC cable aren't knackered up and looking over the motherboard good for any missing components or other signs of damage.