Membrane 3x4 Matrix Keypad

[bluePanda]

Hello,
I recently purchased a Membrane 3x4 Matrix Keypad http://www.adafruit.com/products/419#tutorials, however the [3, 7, 8, 9] buttons do not work. I tested the connections with a voltmeter and did not get any readings. Does anyone have anymore troubleshooting steps? Thanks.

[adafruit_support_bill]

That's unusual. These are pretty simple devices with not much to go wrong on them. Are you sure you are testing the right combination of pins?

If you look closely at the flat conductor cable, you will see it is split into two parts. The 3-conductor part is for the 3 columns. The 4-conductor part is for the 4 rows. Each button just shorts between one row and one column. This photo shows how they are connected (reversed of course since we are looking from the back-side)

Pin 3 should short the center pin to the leftmost (looking from the front) pin.

[bluePanda]

Thanks for your quick response. I took a volt meter and was able to get a reading when pressing down the working buttons. The few that do not work show no change when the button is pressed.I did this outside of any circuit to make sure it wasn't bad wiring or bad programming that displayed a fake error. Are there any other things I can try to diagnose the problem?


Thanks,

[adafruit_support_bill]

Not really much else to diagnose. These are fairly simply devices. If the buttons are not making contact it is probably due to a cracked trace somewhere or some oxidation or other contamination on the contacts.

If you contact [email protected] with a link to this thread we can send out a replacement for you.

[bluePanda]

I just wanted to say, I got my replacement and everything is working perfectly. Thank you for the great support!