This is a blink Level 2 EVSE and it has an issue with the touch-screen. It was installed outdoors and facing the sun for extended periods. I cleaned the touchscreen assembly including the edges.
There are no display issues, but the touchscreen is very finicky, and barely works intermittently. On power-up the EVSE goes through a touchscreen calibration procedure: touch 5 X's (corners + center), followed by 5 O's in the same screen positions. It doesn't accept touches after the 3rd-7th calibration point. The calibration period has a countdown, and then restarts. One time I touched some parts of the screen unintentionally, and it put me straight into the main menu but then it stopped accepting any more touch input.
I don't know the exact touchscreen technology in use, but I highly doubt it's a multi-touch.
Starting from the contact layer the touchscreen is made up of:
1- a clear plastic layer with 4 contacts on the bottom right, and tracings all around. This layer is glued with double-sided tape on the edges to ...
2- a glass assembly with 4 contact points that connect via a 4-wire flat cable to a main board header labelled "touch screen". The glass assembly seen from its side looks to be two layers of glass sandwiched together. It is clear that the center of the screen has an artifact - a square in proportion to the screen dimensions with rounded corners. This doesn't look good, but it is possible to tap on one calibration point in that area, although, I can't tell if the signals generated represent taps in that area.
3- the display panel
I lifted the top clear plastic (what your fingers touch) and cleaned it. I used alcohol, and goof-off on the edges to remove most of the gummy bits of the double-sided tape that held it to the glass. I didn't put new tape when I put the film back, and perhaps this is why it is not working reliably. If I am not mistaken, it should be glued so that it stands off the glass underneath, correct?
I believe the problem is with the mating of the top film to the glass panel. There are "traces" on both the film and the panel, but I am not clear on how those interact to make the touchscreen work. The traces are gray in color, and matte, or slightly rough in texture. I used my multimeter to check continuity between the four contact points and the ends of the traces coming from them, and got no beeps.
Any pointers would be appreciated.
There are no display issues, but the touchscreen is very finicky, and barely works intermittently. On power-up the EVSE goes through a touchscreen calibration procedure: touch 5 X's (corners + center), followed by 5 O's in the same screen positions. It doesn't accept touches after the 3rd-7th calibration point. The calibration period has a countdown, and then restarts. One time I touched some parts of the screen unintentionally, and it put me straight into the main menu but then it stopped accepting any more touch input.
I don't know the exact touchscreen technology in use, but I highly doubt it's a multi-touch.
Starting from the contact layer the touchscreen is made up of:
1- a clear plastic layer with 4 contacts on the bottom right, and tracings all around. This layer is glued with double-sided tape on the edges to ...
2- a glass assembly with 4 contact points that connect via a 4-wire flat cable to a main board header labelled "touch screen". The glass assembly seen from its side looks to be two layers of glass sandwiched together. It is clear that the center of the screen has an artifact - a square in proportion to the screen dimensions with rounded corners. This doesn't look good, but it is possible to tap on one calibration point in that area, although, I can't tell if the signals generated represent taps in that area.
3- the display panel
I lifted the top clear plastic (what your fingers touch) and cleaned it. I used alcohol, and goof-off on the edges to remove most of the gummy bits of the double-sided tape that held it to the glass. I didn't put new tape when I put the film back, and perhaps this is why it is not working reliably. If I am not mistaken, it should be glued so that it stands off the glass underneath, correct?
I believe the problem is with the mating of the top film to the glass panel. There are "traces" on both the film and the panel, but I am not clear on how those interact to make the touchscreen work. The traces are gray in color, and matte, or slightly rough in texture. I used my multimeter to check continuity between the four contact points and the ends of the traces coming from them, and got no beeps.
Any pointers would be appreciated.
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