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Faulty Display

Posted: Thu Jul 07, 2016 8:19 am
by delshay
I Bought two displays & one of the two has been faulty since I got it & is getting worse. I tried to find the HR fault on the PCB as it a pain to send it back.

it was flakey when I got it and it still works (sometimes) , but this is touchscreen and will cut-out when screen is touched.

Fault now traced it to smaller of the two BGA chips. The thing is, I do have the correct equipment to reflow & repair it , but the only problem being sticking the screen back onto the PCB, as screen have to be removed in-order to do reflow.

I have not removed the screen or done a reflow, but I have been tracing the fault with a micro tip soldering iron only to discover it's a BGA soldering fault.

Not sure what to do from here, but if no help arrives, I have no choice but to remove screen & reflow.

Other display has just now being mounted into PC by removing "Cooltouch-E" display & replacing it with GTT38A with just a small modification to the inner part of bracket & sprayed Mat Black.

Re: Faulty Display

Posted: Thu Jul 07, 2016 9:25 am
by Daniel Divino
Hello Delshay,

I understand that one of your displays is cutting out and going black whenever the screen is touched. It's unfortunate to hear that you've been having issues with one of your displays.

Could you specify which display is having issues? If you could provide the model of display you are having issues with, I would greatly appreciate it.

Cheers,
Daniel

Re: Faulty Display

Posted: Fri Jul 08, 2016 12:09 am
by delshay
Daniel Divino wrote:Hello Delshay,

I understand that one of your displays is cutting out and going black whenever the screen is touched. It's unfortunate to hear that you've been having issues with one of your displays.

Could you specify which display is having issues? If you could provide the model of display you are having issues with, I would greatly appreciate it.

Cheers,
Daniel
Both display are GTT38A, bought direct from Matrix Orbital this year, 15 MAY 2016. I have the order number, but not sure if it is safe to post it here.

Re: Faulty Display

Posted: Fri Jul 08, 2016 8:32 am
by Daniel Divino
Hello Delshay,

Are you able to measure the input voltage and current to the display? We've seen situations in the past where a lack of power to the display can cause a reset every time a user touches the screen. This issue usually occurs on our larger GTT50A and GTT70A units due to their higher power requirements, but the GTT38A is not exempt from this either.

If possible, please check the voltage and current input to the display and let me know what you find.

Cheers,
Daniel

Re: Faulty Display

Posted: Fri Jul 08, 2016 2:36 pm
by delshay
When unit is powered on ,there is no display but green power LED is lit. When a little pressure is applied to the smaller of the two BGA chip, it comes on every time & DEMO works while a little pressure is applied to the chip.

When pressure is released, the next time it is powered up, display is not lit, but LED is on . The other display works fine from PC & External power supply, but the second display has a intermittent fault.

Both display tested using same power source.

PC Voltage 4.98V

External power supply 4.85V

Re: Faulty Display

Posted: Mon Jul 11, 2016 9:51 am
by Daniel Divino
Hello delshay,

It does definitely seem like the BGA chip is the issue. I do highly recommend you send the unit to us for repairs. If you purchased the unit within the last year, the repairs and return shipping will be covered under warranty.

That said, if you do have the tools, and the know how on repairing the unit, we cannot stop you from proceeding with the repairs yourself. I will remind you that modifying the PCB in any way (other than moving the protocol select jumpers) will void the warranty on the unit, so repair it at your own risk.

If you do decide to return the unit to us, please let me know, and I will enter an RMA into our system for you.

Cheers,
Daniel

Re: Faulty Display

Posted: Mon Jul 11, 2016 8:59 pm
by delshay
I think I will return the unit. The only jumper that was moved is the one that power the unit, but I can move it back as USB power.

PC here USB is always powered-up, even when PC is off, so display does not switch off when PC is off, when using USB power.

I have full infrared vision base BGA soldering unit, so I can do it myself, but the problem being as already pointed out, how do I stick the screen back on. its stuck to the PCB with what seems like very stiff padding.

would it be ok to leave the power jumper where it is? its powered via the 4 pin floppy connector.

Re: Faulty Display

Posted: Tue Jul 12, 2016 8:36 am
by Daniel Divino
Hi delshay,

Though you would be able to separate the display and the PCB from the foam, you will not be able to re-use the same foam when assembling the display back together again. You would have to find another adhesive to use in order to put the two parts back together.

I'll contact you directly to send you information about the RMA.

Cheers,
Daniel

Re: Faulty Display

Posted: Tue Sep 06, 2016 1:09 am
by delshay
Thanks, faulty display fixed/replaced all is well.