Alpine 3681 Manual De Instalación Y Operación página 23

Remote-on light does not come on.
Remote-On light is on, but no sound is heard
from some or all of the speakers.
Alternator whine through the audio system
with the engine running.
Head unit is not on: Turn the head unit on.
Ground wire is disconnected or defective: Check
for continuity with an ohmmeter between 3681's
Ground terminal and a known chassis ground
point.
Battery wire is disconnected or defective: Check
for approximately + 12 volts between 3681's Bat-
tery and Ground terminals.
Blown Fuse: Check 3681's 5A Fuse, located near
the Battery terminal. If it is blown, replace it with
an identical one. If the new fuse blows immedi-
ately, then check all the wiring connections. If no
fault is found, consult your Alpine dealer.
Remote-On wire between the head unit and the
3681 is disconnected or defective: Check for + 12
volts between 3681's Remote-on connector and
ground connector with the head unit on.
Incorrect Switch Settings: Make sure that all
Mode Selector switches are in their correct posi-
tions for your system configuration (see WIRING
AND SET-UP).
Defective or disconnected audio cables: check for
continuity and replace if necessary.
Incorrect Output Level Adjustment: Verify that the
3681's output level controls are not turned very
low. If they are, sound output level may be very
low and may give the impression that the system
(or part of the system) is dead.
Defective 3681: Bypass the 3681 by connecting its
input and the dead output terminal's cables to-
gether (with a pair of Alpine 4402 female-to- —
female adaptors). If the system becomes func-
tional, the 3681 may be defective. Consult your
Alpine dealer.
Defective Head Unit, or other audio component:
Check each component for wiring and operation.
Ground loops: Connect grounds of all audio com-
ponents to the same point on the vehicle chassis.
Verify that this point is a true ground by checking
for continuity with an ohmmeter between the
ground point and the battery's (—) terminal, and
follow the grounding recommendations on page
17.
Shorted Signal and Chassis Grounds: Check for
shorts between speaker leads and chassis
ground, or input signal ground and chassis
ground.
The other audio components may have insuffi-
cient filtering: They may need noise suppressors
on their battery or ignition connections.
Check the vehicle's battery and voltage regulator.