STERO SD3 Series, Руководство по обслуживанию и запасным частям

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E. MICRO LED is flashing at a rate of 1 sec on,
1 sec off, and the DOOR and LOW WATER
LEVEL LEDs on control board are on.
Shorting J8 terminals together without
having water in the tank may result in damaging the
tank heater.
NOTE: The TANK HEAT (AM) LED on relay board
should be lit when J8 terminals on relay board are
shorted together.
2. Test tank heat circuit by shorting the two
terminals of J8 on the relay board together.
Fig. 29
NOTE: When machine calls for heat, voltage across
J6-7 and ground will be zero or a few millivolts. Circuit
activation can be verified by measuring 5VDC voltage
across the control board +5VDC test pad and J6-7
when the TANK HEAT circuit is active.
A. If heater circuit energizes, remove J8 short
and troubleshoot the control board by
checking voltage output to relay board
across J6-7 (control board) and ground =
0VDC (J6-7 and +5VDC test pad = 5VDC).
1) If voltage measurements indicate
circuit is active, verify wiring to relay
board is correct. If correct, replace
relay board.
2) If voltage measurements are not
present, replace control board.
B. If heater contactor 2CON does not energize,
but TANK HEAT (AM) LED turns on, check
for 120VAC across relay board J1-4 and X2.
1) If 120VAC is present, remove short
across J8 and check remaining tank
heat circuit.
2) If 120VAC is not present, replace relay
board.
SERVICE DIAGNOSTICS
Certain procedures in this section
require electrical test or measurements while power is
applied to the machine. Exercise extreme caution at
all times. If test points are not easily accessible,
disconnect power and follow lockout / tagout
procedures, attach test equipment and reapply power
to the test.
Certain components in this system are
subject to damage by electrostatic discharge during
field repairs. A field service grounding kit is available
to prevent damage. The field service kit must be used
anytime the control board is handled.
1. Lower wash chamber door.
2. Remove FRONT COVER.
3. Open control door.
4. Enter service diagnostics.
A. From power off. Press and hold both PROG
and SELECT switches on the control board
then press and release the ON key on the
keypad. Continue to hold the PROG and
SELECT switches until the display indicates
[ 88 ]. Release the switches.
B. When machine is on and tank temperature
displayed (FILL icon off). Press and hold
PROG switch then press SELECT switch on
control board.
5. Perform tests as outlined under SERVICE
DIAGNOSTICS CHART and OUTPUT TEST on
the following pages.
6. Exit service diagnostics by pressing the OFF key
on keypad.
NOTE: When in service diagnostics mode the wrench
icon will be displayed except during display test. When
service diagnostics are entered, the control board will
display the most recent P and E errors, if errors are
present. A dash ( - ) in place of a number in either the
left or right digit position indicates no error to be
displayed for that digit. Example: If [ - 2 ] were
displayed, the only fault recorded was, "Water not to
float." However, if [ 2 2 ] were displayed, "Rinse
thermistor error" and "Water not to float" have both
occurred.
SD3 Series - TROUBLESHOOTING
F45576 (1015) Page 32 of 37