AccuTouch Product Guide - Elo TouchSystems

If the constant touch data continues, the problem is controller related. If the
touch data stops and then reappears when the touchscreen is reconnected, the
problem is bezel contact, or a shorted touchscreen or cable. Inspect the bezel
for clearance, and adjust the touchscreen or display mounting if necessary.
See “Touchscreen Diagnosis” on page A-65, for analysis of touchscreen
problems, and “Touchscreen Cables” on page A-75, for cable pinouts.
No touch data. When no touch data is reported, the problem may be the
touchscreen, controller, or cabling. The “paper clip” test may be used to
eliminate some of these possibilities. With the appropriate driver or
diagnostic software loaded, connect a straightened paper clip or other
suitable wire to the controller input as follows:
Serial Controller - Connect a wire jumper between pins 2 and 3 or 3 and
4 at connector P3 on the controller board. If you have a touchmonitor with
an internal serial controller, it may not be easy to perform this test. Limited
diagnostics can be performed by looking at the RS-232 output.
See “RS-232 Connections” on page A-71.
If you have a TouchMonitor with an internal serial controller, it may not
be easy to perform the paper clip test. Limited diagnostics can be
performed by looking at the RS-232 output. See “Serial Controller” on
page A-69.
If you are working inside a display with the touchscreen installed, it is not
necessary to disconnect the touchscreen when performing this test. If the
touchscreen is disconnected, ensure that transient protection is still
connected to the touchscreen. If separate transient protection has not been
used and you are disconnecting the touchscreen from the controller,
ground all five pins of the touchscreen cable to chassis ground of the
display.
Bus Controller - Connect the wire jumper between pins 1 and 6 or 1 and 7
of the DB9 female connector on the controller or to the same pins of the
touchscreen cable. See Figure A.4 on page A-79.
The result of this test for either style of controller will be continuous
transmission of touch data if the controller and its link to the host are working.
The values for X or Y will be at or near the maximum value of 4095 for both
serial and bus controllers depending on the connection you have made.
If an extension cable was used for the paper clip test and the controller did not
respond, the touchscreen cable may be at fault. Move the paper clip to the
connector on the controller and repeat the test. See “Touchscreen Cables” on
page A-75.
A lack of response to the paper clip test points to a faulty controller, controller
setup, power supply, or cables, See “Serial Controller” on page A-69, or “Bus
Controller” on page A-74.
A-64 IntelliTouch/SecureTouch Guide