Appendix C - Troubleshooting
This troubleshooting guide is written with the as- sumption that the user has read and understood the relevant sections in this manual.
It is possible in many cases to solve difficulties without having to send the display unit back to the manufacturer for repair. Please follow this troubleshooting section before contacting the nearest Navman dealer.
There are no user serviceable parts. Specialized methods and testing equipment are required to ensure that the display unit is reassembled cor- rectly and is waterproof. Users who service the product themselves will void the warranty.
Repairs to the product may only be carried out by a service centre approved by Navman. If the product must be sent into a service centre for repair, it is essential to send in the transducer(s) at the same time.
More information can be found on our Website: www.navman.com.
1. The fishfinder won’t turn on:
a)The FISH 4500/4600 is designed to operate on a 12/24 volt battery system, where the voltage may vary from 10 to 35 volts. If an excessive voltage is supplied, a fuse will be tripped, turning the display unit off. Check the fuse.
b)Check that the power cable connector at the back of the display unit is securely plugged in and the collar is locked in place. The collar must be secure for watertight connection.
c)Measure the battery voltage while the battery is under load - turn on some lights, radio or other electrical equipment connected to the battery. If the voltage is less than 10 volts:
-the battery terminals or wiring on the terminals may be corroded.
-the battery may not be charging cor- rectly or may need replacing.
d)Inspect the power cable from end to end for damage such as cuts, breaks, squashed or trapped sections.
e)Ensure that the red wire is connected to the positive battery terminal and the black wire to the negative battery terminal. If wired for theAuto Power option, ensure the yellow wire is connected to the ignition circuit. Also check the boat’s main switch circuit (see section
f)Check for corrosion on the power cable connector and clean or replace if required.
g)Check fuses that are placed in line with the power cable. A fuse can be blown despite appearing to be good or the fuse may be cor- roded. Test the fuse or replace it with a fuse known to be good.
2.The fishfinder won’t turn off:
The fishfinder may have been wired forAuto power. In this case, the fishfinder cannot be turned off while the ignition power is on. (See Auto power wiring in section
3.The fishfinder operates erratically:
a)Check that the transducer does not have de- bris (e.g. weed, plastic bag) caught around it.
b)The transducer may have been damaged during launching, running aground or while underway with debris etc. If the transducer has been impacted, it may have been kicked up on the bracket. If it is not physically damaged, reset the transducer back to its original posi- tion. (See the Transom Transducer Installation Guide.)
c)When the transducer is less that 2 ft. (0.6 m) from the bottom, the depth readings may become inconsistent and erratic.
d)Manual Gain may be set too low, which may cause weak bottom echo or no fish signals. If in Manual Gain, try increasing the Gain.
e)Ensure the back of the bottom surface of the transducer is slightly lower than the front and the front is as deep in the water as possible in order to minimize the generation of bub- bles through cavitation. (See the Transom Transducers Installation Guide.)
f)Check the transducer and power cable connectors at the back of the display unit are securely plugged in and the collars are locked in place. The collars must be secure for watertight connection.
g)Inspect the power cable from end to end for damage such as cuts, breaks, squashed or trapped sections.
h)Ensure there is not another fishfinder or depth sounder turned on, which may interfere with this fishfinder.
i)Electrical noise from the boat’s engine or an accessory may be interfering with the transducer(s) and/or the Navman fishfinder. This may cause the fishfinder to
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