Self-Test Stage 4 - Raytheon ST60 Service Manual

2 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 transducer must be connected for this test.
A. The unit should display 'TEST 4' for 1 second.
B. Transducer test is performed.
Spin the paddle wheel within 15 seconds of entering this test. If the interface is
working correctly, "PASS" will be shown. Otherwise "FAIL 10" is shown.
If the test fails, do the following:
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
Press Key 1 and Key 2 together momentarily to exit self-test.
Part 1. ST60 Instruments – Chapter 1. Speed
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.
Action
Check TR17, TR20, R63 and R64.
Replace L7
Replace D3
Check L9 for open circuit
Check R14
Check TR4.
Check R74, 17