Raymarine ST40 Bidata Owner's Handbook Manual page 19

Chapter 2: Maintenance and Fault Finding
Display blank
D D D D D epth reading
flashes when
under way
No depth information
ST40 BIDATA
D4738-2
ST40
Action
Ensure that reading stabilises when clear of disturbed water,
e.g. boat wakes, propeller wash etc.
ST40
1 minute
ST40
Action
Check the condition of the depth transducer cable and the
security of the connections.
Could also be due to weed growing on the transducer face.
Action
Check fuse/circuit breaker.
Check power supply.
Check SeaTalk cabling and
connector security.
OR
BIDATA
ST40
OR
BIDATA
ST40
ST40
BIDATA
11
BIDATA
D4739-2
BIDATA
1 minute
BIDATA
D4740-2