Sperry Marine NAVIKNOT 600 SD, Operation, Installation And Service Manual

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NAVIKNOT 600 SD 056353/J
NAVIKNOT Electronics Unit and CDU(s) 8-1
Chapter 8: Troubleshooting
8.1 NAVIKNOT Electronics Unit and CDU(s)
The NAVIKNOT 600 SD electronics unit and the CDU are complex elec-
tronic devices. In case of malfunction, it would neither be practical nor
economical to carry out troubleshooting and servicing in the field down
to the level of individual circuit components.
Unless instructed otherwise by Sperry Marine engineering, field service
personnel should limit troubleshooting to the basic checks given below.
• For the electronics unit:
– Visual inspection of mechanical components, the processor and
satellite PCBs and wiring.
– Continuity checks of wiring connections.
– Checks for short circuit or overload conditions or reversed polar-
ity of the external supply powers.
– Checks of the on-board supply voltages and I/O signals and data.
The presence of voltages, signals and data is indicated by diag-
nostic LEDs on the PCB.
Exact voltage levels must be checked with a voltmeter.
The data content on serial I/O lines must be checked with the aid
of suitable analyzing tools, such as PC-based protocol interpret-
ers or terminal programs.
When components on the processor PCB, other than socketed ICs or
the exchangeable system software flashboard, are assumed to cause
malfunction, the complete PCB, Stock No. 20692, is to be exchanged.
When malfunction of the satellite PCB is assumed, the complete
PCB, Stock No. 20711 is to be exchanged.
If malfunction of the electronics unit cannot be tracked down to one
of the PCBs, the electronics unit as a whole is to be exchanged.
• For the CDU(s):
– Visual inspection of mechanical components and wiring.
– Continuity checks of wiring connections at the terminals or ter-
minal block to which the 6-wire CDU connection cable is fas-
tened.
– Checks for the presence and correct polarity of the external sup-
ply power.
The CDU is not field-serviceable and should not be opened for trou-
bleshooting purposes. Defective CDUs must be sent back to Sperry
Marine for repair.
CAUTION
Risk of damage through unauthorized service.
The NAVIKNOT electronics unit and CDU unit are generally not field-ser-
viceable on the component level. Defective units must be returned to
Sperry Marine for exchange.
Any service work on the electronics unit or CDU is to be carried out by
authorized service personnel only.