Chapter 8
MDC-1840BB/1841BB/1860BB/1810BB/1820BB Series
Trouble Shooting And On Board Servicing
Operation Manual
8-4
93142122-07
Description of faults
Possible cause of failures
Corrective measures
Aerial does not rotate
1. Motor fuse is blown.
2. Turning motor is not powered.
3. Turning motor brushes are worn
out.
1. Replace the motor fuse
with new one.
2. Check the connections for
motor power supply line.
3.
Replace the motor
brushes.
8.3.2 Faultfinding chart
The following faultfinding charts are prepared for a service engineer to allow him to
diagnose and locate a faulty part on a module basis. The charts are systematically
arranged from primary fault analysis to finding a path to a detailed flow chart that
follows.
1. Fault analysis
Y
N
Go to “3. No display”
Go to “2. No response”
N
Y
Go to “4. Antenna does
not respond”
N
Go to “7. Fault Panel”
Y
N
Go to “6. Fault Interface”
Go to “5. Faulty radar picture”
N
Y
Y
N
Is the entire screen
presentation normal?
N
Go to “8. Others”
N
Y
Go to “9. Antenna faults”
Does the display turn
on?
Does a short beep
sound?
Is the echo shown on
the screen?
Are key switches or
control operative in
normal manner?
Turn the system on
Start
Transmit the radar
Does the display switch to
STANDBY mode?
Is any error message shown
in North-up, Course-up or
True Motion mode?
Is the fault connected
with external serial data?
Other faults
