Raymarine ST40 - Self-Test Stage 2; Self-Test Stage 3

Part 2 Instrument Servicing
2-10 ST40 Instruments Service Manual 83149-2
E22038
If the tests are not satisfactory, the following failure codes may be generated:
Message Failure Mode Action
FAIL 8 SeaTalk Rx/Tx Check for damaged bucket connectors/rear-case pins.
Check SeaTalk interface components around TR1, TR2 and TR3.
FAIL 18 EEPROM failure Replace EEPROM (IC2)
If there is no audible beep, check TR19(b) and RN3 and the buzzer for damage. If the
beep volume is low, check R93.
Press the and keys together momentarily, to proceed to self-test stage 2.
Self-test stage 2
When entering self test stage 2, the instrument beeps and the display shows TEST 2,
for 1 second. The following tests are then performed automatically:
• The display backlighting cycles between on and off every second.
• A display test is performed. The LCD segments are displayed in the following
sequence, changing once per second:
CAL
D4887-1
While this test is progressing, press each of the front panel keys and check that the
buzzer sounds as each key is pressed.
If any problems occur, use the following table as a guide to try to remedy the
problem:
Failure Action
No illumination Check TR18 and associated components.
Check all LEDs.
No beep when key pressed Replace keyswitch.
LCD segment(s) missing completely Check LCD pins for poor/dry joints.
Check IC7 pins for poor/dry joints.
Faint LCD segments Check LCD for short circuited pins.
Check IC7 for short circuited pins.
Check the contrast drive circuit around TR6.
Press the and keys together momentarily, to proceed to self-test stage 3.
Self-test stage 3
Note: A known good depth transducer should be connected and placed in water, for
this test. If this is not possible, an echo simulator can be used.