ADC AD-81 Service Manual page 47

Phase 5 OPL Microprocessor Controller (Computer) Relay Output
Light Emitting Diode (L.E.D.) Indicators
There are a series of five (5) L.E.D.
indicators (red lights) located at the lower
back side area of the Phase 5 OPL
microprocessor controller (computer).
These are identified or labeled from left
to right in the illustration as "HEAT,"
"MTR" (motor), "FWD" (forward),
"REV" (reversing), and "DOOR."
These L.E.D.s indicate that the outputs
of the Phase 5 OPL microprocessor
controller (computer), or, in the case of
the door switch input, are functioning.
1. "DOOR" L.E.D. Indicator
a. SHOULD BE ON ALL THE TIME (even if the dryer is not running) unless the main door is open or
there is a problem (open circuit) in the main door switch circuit.
NOTE: If the dryer is started (display indicator dots are on) and there are no outputs ("HEAT" and/or
"MTR" output L.E.D.s are off) and the "DOOR" input L.E.D. is on; then the fault is the
Phase 5 OPL microprocessor controller (computer) itself.
If the failure was elsewhere (i.e., the dryer's door switch circuit), the L.E.D. display would
read "door" if a keyboard (touch pad) entry was attempted.
If the display indicator dots are on, and the "DOOR" L.E.D. input and the motor/heat output
L.E.D.s are on, yet the motor and/or heat is not active (on); then the problem is elsewhere in
the dryer.
2. "HEAT" Output L.E.D. Indicator
a. If the dryer is started and there is NO "HEAT," yet the Phase 5 OPL microprocessor controller
(computer) display heat circuit indicator dot is on, but the "HEAT" output L.E.D indicator is off; then
the fault is the Phase 5 OPL microprocessor controller (computer) itself.
1) If both the display indicator dot and the " HEAT" output L.E.D. indicator dot are on; then the
problem (fault) is elsewhere (i.e., external to the Phase 5 OPL microprocessor controller [computer]).
3. "MTR" Output L.E.D. Indicator
a. If the dryer is started and the blower (impellor/fan) motor is not operating, yet both the Phase 5 OPL
microprocessor controller (computer) display blower (impellor/fan) motor indicator dot and "DOOR"
input L.E.D. indicator dot is off; then the fault is the Phase 5 OPL microprocessor controller (computer)
itself.
43