
9. MAINTENANCE & TROUBLESHOOTING
9-6
Display test
1) Press [MENU ESC], [8] and [3] to display
the test pattern screens.
2) To change the test pattern, press the
[NU/CU ENT] key. Each time the key is
pressed one of the patterns shown in
Figure 9-12 appears.
TEST PATTERN
ENT:Pattern MENU:Escape
Figure 9-12 Test patterns 1 and 2
3) To quit the test pattern, press the
[CLEAR] key three times. Control is
returned to the SELF TESTS menu.
4) Press the [MENU ESC] key.
Automatic testing
This feature conducts all self tests
continuously.
1) Press [MENU ESC], [8] and [4]. Self tests
are conducted continuously in the order
of memory, I/O test, keyboard test and
test pattern.
2) To stop testing, press the [MENU ESC]
key.
3) Press the [MENU ESC] key.
9.6 Interface Unit IF-2500
Fuse replacement
If the fuse blows, find the cause of the
problem before replacing it. Do not use a
fuse rated more than 0.5A, since it may
cause more serious damage to the
equipment.
Self test 1
The unit performs an internal self-check in
the following sequence each time power is
turned on.
1) LEDs CR7 to CR10 blink twice every 2
seconds.
2) ROM and RAM are tested.
3) LED CR13 blinks every second for
normal operation. If an error is detected
during the test, the corresponding LED is
turned on.
•
When CR7 is on, ROM is defective.
•
When CR8 is on, RAM is defective.