PolyPlanar MRD85i - Manual (Page 21)

21
T R O U B L E S H O O T I N G
PROBLEM CAUSE CORRECTIVE
ACTION
No power Blown fuse, power
wires disconnected Check the fuse and
power wire or ground
wire connection
No sound Mute is on, Volume set
at minimum, wiring is
not properly connected
Turn Mute to off, adjust
volume to a desired
level, check the
speaker wire
Cannot read some
USB devices This unit is not 100%
compatible with all
USB devices or the
USB devices has
special format. Try to format the USB
device in FAT 16/32
standard
Unit powers off by
itself The battery may be too
low (the unit operating
voltage is 10.8v to
15.6v).
Unit takes about 45
seconds to
recognize some
USB device or SD
card This is normal. The
unit sometimes takes
longer time to read all
the files inside the USB
device or SD Card. Try to remove the USB
device or memory card
and insert it again.
Operations keys do
not work Press the RESET
button
The unit picks up
engine noise. Check the ground wire.
The radio does not
work. The radio
station automatic
selection does not
work The antenna cable is
not connected or the
signals are too weak Insert the antenna
cable firmly or select a
station manually