MikroTik RB450G User Manual

RB doesn’t boot, green and blue LED’s is shine
The board is unrepairable
Change faulty crystal oscillator
NO 40MHz
Problem
still appears
Change faulty ferrite beads
Check 2.5V output,
for example on C849 pins
Check CPU core 1.2V output,
for example on C853
Check 40MHz clock on crystal
oscillator Y301 pin#3
Check ferrite beads FB801, FB806
resistance. It should be less than 1 Ohm
Change faulty DC-DC Step-Down
converter U805
OK
NO 2.5V NOT OK
Check ferrite beads FB802, FB803
resistance. It should be less than 1 Ohm
NO 1.2V
Change faulty DC-DC Step-Down
converter U806
OK
Try to change RAM memory
U201-U204
PoE does not work
Change faulty diode bridges
Check diode bridges
D805, D806
OK
NOT OK
Change faulty connector
Check connector
J504
NOT OK
The board is unrepairable
Problem
still appears
Change faulty ferrite beads
NOT OK
OK
OKOK
Try to change processor
U1
OK
Change faulty ferrite beads
Check ferrite beads FB701, FB702 resistance.
It should be less than 1 Ohm
OK
NOT OK
NOT OK
Change faulty ferrite beads

MikroTik RB450G Specifications

General

Wi-Fi band	-
Storage media	Flash
Internal memory	256 MB
Storage capacity	512 MB
Voltage monitoring	Yes
License level	5
Processor cores	1
Processor model	AR7161
Processor frequency	680 MHz
Compatible memory cards	MicroSD (TransFlash)
Basic switching RJ-45 Ethernet ports type	Gigabit Ethernet (10/100/1000)
Power over Ethernet (PoE) voltage range	8 - 30 V
Power connector	DC-in-jack
DC input voltage	8 - 28 V

Weight and Dimensions

Depth	115 mm
Width	90 mm
Weight	105 g