Raytheon ST60, Service Manual

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Part 1. ST60 Instruments – Chapter 4. Tridata
A22004
26 ST60 Instruments Service Manual 83142-1
No fail codes are generated since stage 2 is an audio/visual check. The following can,
however, be used as a guide to isolate a problem:
Failure Mode Action
No illumination Check TR14, TR13, TR15 and associated components. Check all LEDs.
Keypad Illumination failure (LCD Check TR14, TR13, R22 and R23.
illumination will also be degraded). Check LED1-6 for open circuit.
Keypad illumination OK Check TR14, TR15, RN3, R24.
but degraded LCD illumination. Check LED 7 and 8 for open circuit.
No beep when key pressed. Replace keyswitch.
LCD segment(s) missing Check LCD solder pins for poor/dry joints.
completely. Check IC3 for unsoldered pins.
Faint LCD segments Check LCD pins for shorts.Check IC3 for shorts.
Press Key 1 and Key 2 together momentarily to progress to self-test stage 4 (stage 3
not supported on this instrument).
Self-test stage 4
Note: A known good speed and depth transducer must be connected for this test.
A. The unit should display ‘TEST 4’ for 1 second.
B. Transducer tests are performed.
Spin the paddle wheel within 15 seconds of entering this test. If there is a problem with
the speed interface “FAIL 10” is shown and the following tests should be carried out.
Check Failure Mode Action
Voltage at 12V_SPD No voltage or low voltage (<11.0) Check TR17, TR20, R63 and R64.
with 12V battery supply.
L7 Open circuit Replace L7.
D3 Open circuit Replace D3.
Voltage at TEMP pin Outside acceptable range of Check L9 for open circuit.
0.76 to 1.00V (18 - 25 degrees C) Check R14.
AVREF Outside acceptable range of 2.5V +/- 0.25v Check TR4. Check R74, 17.
Provided the depth transducer is in water where a good echo should be seen, the test
will pass, otherwise “FAIL 8” is shown and the following tests should be carried out:
Check Failure Mode Action
Pulses at pins 8 and 10 of IC4 No pulses Check R68, 76, 77. Check IC4 and IC5 and
replace if suspect (trace pulses from IC3).
Pulses at drain of TR5 No pulses Check L5 and R19 for open circuit.
Replace TR5. Replace T1.
Pulses at drain of TR6 No pulses Check L5 and R19 for open circuit.
Replace TR6. Replace T1.
Pulses at DEPTH+ and DEPTH- No pulses Check C11 and C12 for open circuit. Replace T1
Depth receiver output pulses No pulses Fault diagnosis of the depth receiver circuit
at pin 11 of IC5 requires specialist knowledge and the units
should be returned to Raytheon Marine Ltd.
Press Key 1 and Key 2 together momentarily to exit self-test.