TroubleShooting for RB433r3, RB433Ur2
These repair instructions are for NON WARRANTY
repairs only!
No power, blue LED isn’t lit
Please make visual inspection for signs of corrosion or
mechanical damages before starting.
Check Schottky diode D802
Change faulty diode D802
NOT OK
O
K
Check Zener diode D804
Change faulty components
Check PNP transistor Q802 and
Zener diode D803
OK
O
K
NOT OK
Check P-channel MOSFET
Q801
NOT OK
Change faulty P-channel
MOSFET Q801
O
K
Check R819 resistor resistance.
It should be 10 Ohm
NO 10 Ohm
Change faulty resistor
R819
O
K
Check PWM controller U803.
On the pin#1 should be 4.4-
5.0V
NOT OK
Change faulty PWM
controller U803
O
K
Check N-channel MOSFET’s
Q806, Q808
NOT OK
Change faulty MOSFET’s
Check short circuit on 1.8V,
for example, on C612 pins
O
K
Short circuit
Unsolder Ethernet Switch U601
and check 1.8V for short circuit
O
K
Change faulty Ethernet
Switch U601
The board is unrepairable
Problem still
appears
Summary of Contents for RB433r3
Page 5: ...RB433r3 Reference picture ...
Page 6: ...RB433r3 Reference picture ...
