Self-Test Stage 4 - Raytheon ST60 Service Manual

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
No illumination
Keypad Illumination failure (LCD
illumination will also be degraded).
Keypad illumination OK
but degraded LCD illumination.
No beep when key pressed.
LCD segment(s) missing
completely.
Faint LCD segments
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
Voltage at 12V_SPD No voltage or low voltage (<11.0)
with 12V battery supply.
L7 Open circuit
D3 Open circuit
Voltage at TEMP pin Outside acceptable range of
0.76 to 1.00V (18 - 25 degrees C)
AVREF Outside acceptable range of 2.5V +/- 0.25v
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
Pulses at pins 8 and 10 of IC4
Pulses at drain of TR5
Pulses at drain of TR6
Pulses at DEPTH+ and DEPTH-
Depth receiver output pulses
at pin 11 of IC5
Press Key 1 and Key 2 together momentarily to exit self-test.
Part 1. ST60 Instruments – Chapter 4. Tridata
Action
Check TR14, TR13, TR15 and associated components. Check all LEDs.
Check TR14, TR13, R22 and R23.
Check LED1-6 for open circuit.
Check TR14, TR15, RN3, R24.
Check LED 7 and 8 for open circuit.
Replace keyswitch.
Check LCD solder pins for poor/dry joints.
Check IC3 for unsoldered pins.
Check LCD pins for shorts.Check IC3 for shorts.
Failure Mode Action
No pulses Check R68, 76, 77. Check IC4 and IC5 and
replace if suspect (trace pulses from IC3).
No pulses Check L5 and R19 for open circuit.
Replace TR5. Replace T1.
No pulses Check L5 and R19 for open circuit.
Replace TR6. Replace T1.
No pulses Check C11 and C12 for open circuit. Replace T1
No pulses Fault diagnosis of the depth receiver circuit
requires specialist knowledge and the units
should be returned to Raytheon Marine Ltd.
Action
Check TR17, TR20, R63 and R64.
Replace L7.
Replace D3.
Check L9 for open circuit.
Check R14.
Check TR4. Check R74, 17.