Self-Test Stage 3 - Raymarine ST40 Service Manual

Chapter 4, ST40 Wind Instrument
ST40 Instruments Service Manual 83149-2

Self-test stage 3

Note: A known good Rotavecta transducer must be connected, for this test.
When entering self test stage 3, the instrument beeps and the display shows TEST3,
for 1 second.
A transducer test then starts. Within the next 15 seconds, manually spin the
Rotavecta cups, so they rotate at approximately 20 rpm, or faster.
If the instrument detects a sufficient number of Rotavecta pulses, PASS is shown on
the display.
If the test fails, FAIL 36 is displayed. Use the following table to try to isolate the cause.
Check
Rotate Rotavecta cups and
check that the voltage at P2
switches between approx 3 V
and 8 V
Check Rotavecta pulses at
IC4, pin1
Check ROTAPRESS at
IC4, pin 2 is high.
Press the and keys together momentarily to exit self-test.
Failure mode Action
Voltage not switching Check constant current at P2 is approx 10 mA
Check that P1 is at 0 V
Check L7 is not open circuit.
No pulses Check IC4 and associated
components
ROTAPRESS low Check IC4 and associated
components.
2-31