Daikin Super Multi Plus D-Series, Service Manual

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SiEBE18-526 Troubleshooting for Outdoor Unit
Troubleshooting 307
7.14 Malfunction of Low Pressure Sensor
Remote
Controller
Display
JC
Applicable
Models AII outdoor unit models
Method of
Malfunction
Detection
Malfunction is detected from pressure detected by low pressure sensor.
Malfunction
Decision
Conditions
When the low pressure sensor is short circuit or open circuit.
Supposed
Causes „
Defect of low pressure sensor
„ Connection of high pressure sensor with wrong connection.
„ Defect of outdoor unit PCB.
Troubleshooting
∗
1: Voltage measurement point
∗
2: Refer to pressure sensor, pressure/voltage characteristics table on P328.
(Q0434)
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
The
relationship
between the
∗
1
VL and low pressure is
normal (see
∗
2) when voltage
is measured between X45A pins
(2) and (3) of outdoor unit
PCB (A1P)
(see
∗
1).
Replace the low pressure sensor.
Connect low pressure sensor
property and restart system.
NO
NO
Replace outdoor unit PCB A1P.
YES
YES
The low
pressure sensor is
connected to X45A (blue)
of outdoor unit PCB
(A1P).
Outdoor unit PCB A1P
GND
Lo
w pre
ssu
re
s
en
s
or
(Q0435)
Red
Black
White
4
3
2
1
+5V
X45A
Microcomputer
A/D input
*2 Measure voltage here.