Specifications

Maintenance
MICOM-H Owner’s Guide 49
Troubleshooting
If the radio is malfunctioning, try to solve the problem as follows:
Problem Troubleshooting
Blank Display Check whether:
• DC power cable is connected properly to the radio and
battery.
• A 7.5A fuse is installed in the fuse holder located on the
green wire of the DC power cable.
Display present
but weak or no
receive signal or
noise
Check whether:
• Connection of antenna to antenna tuner and antenna tuner
to radio cables (loose or broken connections).
• Correct programming of operating channel (frequency,
mode of operation, etc.).
Engine noise
picked up by the
antenna
Determine by observing difference in the reception by turning
the Engine ON/OFF.
Ver i fy t h at :
• The ground leads are properly connected, all power wires
and ground leads are as short as possible
• The Noise Blanker (if installed) is enabled.
If the problem persists:
• Install noise reduction Kit TLN8845.
Poor or no
transmission
Check whether:
• A 30A fuse is installed in the fuse holder located on the red
wire of the power cable.
• Proper grounding cables are connected from the radio and
from the antenna tuner to the vehicle chassis.
• While speaking, check RF power bars for activity.
The resulting RF power output is displayed in approximately
15 W increments (bars) being added from the bottom of the
display upwards.
• Three or more bars disappear from the RF power bar display.
There may be a problem in the antenna system. If the
antenna cabling or the antenna mast rigging position has
changed since the antenna was last tuned, the antenna tuner
will not be adjusted automatically. To retune the antenna
tuner, press the ENTER key. If transmission is still poor,
inspect the tuner, antenna and ground plane for loose
connections or misplaced parts. If no loose connections are
found, call your service representative for assistance.
• There are no bars at the RF power bar graph. Indicates low
transmitter power, which can be caused by a faulty
microphone, faulty transmitter, overheating, or defective
antenna system.