Cetrek PROPILOT 700, Installation And Servicing Manual

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PROPILOT 700 INSTALLATION & SERVICING MANUAL
807-007-5-96
TROUBLESHOOTING GUIDE
IN AN EMERGENCY
Press the OFF key or switch the Light Duty Supply off to
regain manual control.
1. Do not connect or disconnect wiring to the terminal
blocks without first ensuring that the supply is turned
off. Certain components will be seriously damaged if
shorted out inadvertently.
2. When first installing or when changing the wiring
always double check the colour coding before switching
on the power.
3. Do not use a simple voltmeter to attempt to check
powered up Digital logic lines or signal lines unless
specifically described in the following discussion.
4. Ensure that all cable screens are properly earthed.
5. Check the fuses and replace blown ones with direct
equivalents. Most units have one internal fuse, the
Distribution Box has 3.
6. Take suitable precautions when handling PCB’s with
Static Sensitive Devices.
7. Read the ‘Good Wiring Practice’ advice in the ‘Installing
Your Autopilot’ section earlier.
Faults Possible cause and remedy
Check the power supplies to the Distribution Box.
In the Distribution Box PCB:
Check Fuse 1. Check the supplies from the Distribution Box
(Brown and Violet wires at PORT B). Check that the link to
the Brown wire, (is at 0V) when you turn the autopilot on,
if not, then suspect fault in the wiring.
Check that the Violet wire is at +5V when you turn the
autopilot on. If this is not so then a fault with the wiring or
Distribution Box PCB is likely.
If new software has just been fitted, check the IC legs.
Damaged legs will probably mean a damaged eprom.
The Fail Safe Watchdog is causing system software to stop
working. A fatal fault has been detected on the Distribution
Box PCB. Remove the top cover and internal RFI shield
from the Distribution Box. Visually check that the socketed
IC’s (IC13 MPU, IC11 Eprom, and IC9 PGA) are installed
1. The system will
not power up.
2. The display
works momentarily
then blanks or the
keys stop working.
Troubleshooting Guide