Trouble Shooting; First-Line Faultfinding - Koden MDC-1840BB Operation Manual

MDC-1840BB/1841BB/1860BB/1810BB/1820BB Series
Operation Manual

8.3 Trouble shooting

This section provides information required to fix or diagnose the faulty part in
MDC-1860BB/1810BB/1820BB radar systems.

8.3.1 First-line faultfinding

Use the following tables that show brief diagnosis schedule to assist first-line servicing
on board the ship.
Table 8.3 Primary faults
Description of fault
Radar does not turn on
Radar turns on but
nothing displayed on the
screen
Table 8.4 Possible faults
Description of faults
Screen is dark
No targets shown
Targets are weak
No markers (HL, EBL,
VRM, Range Rings,
Parallel Index Line,
Alarm Zone)
Heading Line is missing
93142122-07
Possible cause of failure
1. Power cable is disconnected.
2. Power supply voltage is outside of
the specified value.
3. Main fuse is blown.
1. Brilliance control
minimum position.
2. LCD is defective.
3. LCD driving circuits are defective.
Possible cause of failures
1. Brilliance of the screen is not
properly set.
2. LCD driving circuits are defective.
1. Tuning is deviated.
2. Video contrast is poor.
3. Transceiver is defective.
1. Tuning has drifted.
2. Magnetron or MIC is faulty.
1. Marker video contrast
properly set.
2. Logic board is defective.
1. Heading Line signal is not applied to
the display.
2. Heading Line signal
generated. Fault on HL Generator
PCB.
Trouble Shooting And On Board Servicing
Corrective measures
1. Connect the power cable and
secure
connection.
2. Use properly rated power
supply.
3. Replace the fuse with new
one.
is set at 1. Turn the brilliance control CW
to set proper brilliance.
2. Call for service.
3. Call for service.
Corrective measures
1. Turn the brilliance control
CW to set proper brilliance.
2. Call for service.
1. Re-adjust tuning referring to
para 6.2.14 and 6.2.15 in
this manual.
2. Re-adjust contrast referring
to para 6.2.1
3. Turn
Monitor to isolate the faulty
section.
4. Call for service.
1. Re-adjust tuning referring to
para 6.2.14 and 6.2.15 in
this manual.
2. Call for service.
is not 1. Re-adjust Marker contrast
referring to para 6.2.2.
2. Call for service.
1. Check for cable connections
for HL signal at antenna and
is not display units.
2. Call for service.
Chapter 8
the cable plug
on Performance
8-3