check this). The receiver should be able to receive the instructions accurately.
3)、Common fault
(1) key failure
Testing method
make sure the unit running, installed battery to remote control, press various function keys.
Fault judgement
a), if multiple buttons are not work,the main reason is for the bad chip.
b), if sometimes normal, and sometimes fail, then the main reason is the underlying part has a impurity.
(2) No emission signal
Testing method:
make sure the unit running, installed battery to remote control, press various function keys.
Fault judgement
If the remote control without signal, but the display and other functions are normal,then most of the
reason is that a bad emission tube. If the display is not normal, normally chip damage.
(3) Testing method:
make sure the unit running, installed battery to remote control, press various function keys.
Fault judgement
If the remote control is neither transmit nor display,means chip resistors, chip capacitance, crystal 1
(iron crystal) and other damage, If you press reset button, remote control full screen then back to not
show the status, then the most for crystal 2 (ceramic oscillator) is damaged.
(4) Show insufficiency
Testing method:
make sure the unit running, installed battery to remote control, press various function keys.
Fault judgement
If the remote control showing the insufficiency phenomena that are mostly liquid crystal rupture,
leakage and other causes.
4)、electrical properties
(1) tandem the ammeter with remote control, in the DC 3.0V voltage ,if unit can not launch a signal,in
the unit with liquid crystal display,the quiescent current ≤ 70uA, in the absence of liquid crystal
display , the quiescent current ≤ 20uA.
(2) under the voltage of 2.6V,remote control should be able to work properly. In not more than 80% of
the rated voltage (2.4V),the LCD of remote control should be able to clearly show.
7、four-way valve
Visual inspection: pull coil of each power cord, wires should be no break phenomenon;
2)、DCR
(1) turn-to-turn short circuit:
check by multimeter, select the appropriate range, measure the resistance.if the resistance
smaller than the standard resistance.it means four-way valve turn-to-turn short circuit.
(2) coil Open circuit:
check by multimeter, select the appropriate range, measure the resistance.if the resistance is ∞, .it
means four-way valve open circuit.