User Guide

CCS Technical Documentation Troubleshooting Instructions
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Continue
Is the UI-module
keys working?
Try to change UI
PWB. Are the
keys working
now?
Retest failing
UI-module
Check X301 (solder
joints and spring
contacts). Is it OK?
Check lines ROW0 -
ROW4 from X301.
If OK, change Z300. If
still fails, change UPP
Illumination
fault
Measure ROW0 - Row4
lines from X301. Are
voltage level ~1.8V?
No
No
Yes
Measure
SLEEPX-signal from
testpoint J403 when
key is pressed.
Is voltage level
~1.8V?
Yes
When keypad is
pressed, are the
LED’s turned on?
Yes
No
No
End
Change X301
No
Yes
No