Sanyo TH2672R, UH2672R Service procedures Details of Alarm Messages, Alarm P29, MDC trouble

4. Service procedures

4-3. Details of Alarm Messages

(1) [Alarm “P29”]	Input power detection circuit trouble
(MDC trouble)	Compressor does not run.
	Breakdown
	Motor current detection circuit trouble

4

Is power OK?	No	Correct power line.
Yes
Is
current	No	Check and correct
detection
circuit wiring		wiring.
OK?
Are
wiring and	No	Check and correct
connector
		wiring.
connections
OK?
Yes

Is No compressor

OK?

Ground Yes

fault?

Yes

Coil

resistor Yes short circuit?

Coil open	Yes
circuit?
No

Is there

abnormal refrigerant No Replace

accumulation?compressor.

Yes
Is		Are
operation of
	No	C1 and TS No
electronic
		sensors
control valve
		OK?
OK?
Yes		Replace electronic
		control valve.
Is there overload?	No	Remove
		the cause.
Yes
Replace outdoor
unit control PCB.

IV-8

Replace compressor.

Replace C1 and

TS sensors.

SM831148