JL Audio XD 1000/1v2 Manuel D'utilisation page 8

APPENDIX D: TROUBLESHOOTING
"How do I properly set the input sensitivity on my amplifier?"
Please refer to Appendix A (page 12) to set the input sensitivity for
maximum, low-distortion output.
"My amplifier doesn't turn on."
Check the fuse, not just visually, but with a continuity meter. It is
possible for a fuse to have poor internal connections that
cannot be found by visual inspection. It is best to take the
fuse out of the holder for testing. If no problem is found with
the fuse, inspect the fuse holder.
Check the integrity of the connections made to each of the
"+12VDC," "Ground," and "Remote" terminals. Ensure
that no wire insulation is pinched by the terminal set screw
and that each connection is tight.
Check to make sure there is +12V at the "Remote" connection of the
amplifier. In some cases, the turn-on lead from the source unit
is insufficient to turn on multiple devices and the use of a relay
is required. To test for this problem, jump the "+12VDC" wire
to the "Remote" terminal to see if the amplifier turns on.
"I hear a repetitive ticking or popping sound coming out of the speaker(s)."
Check the speaker wires for a possible short, either between the
positive and negative leads or between either speaker lead
and the vehicle's chassis ground. If a short is present, you will
experience distorted and/or attenuated output. The "Status
LED" will turn amber in this situation. It may be helpful to
disconnect the speaker wires from the amplifier and use a
different set of wires connected to a test speaker.
Check the nominal load impedance to verify that the amplifier is
driving a load equal to or greater than 2 ohms.
"My amplifier's output fluctuates when I tap on it or hit a bump."
Check the connections to the amplifier. Make sure that the
insulation for all wires has been stripped back far enough to
allow for a good contact area inside the terminal block.
Check the input connectors to ensure that they all are making good
contact with the input jacks on the amplifier.
14 | JL Audio - XD1200/1v2 Owner's Manual
"My amplifier shuts off once in a while, usually at higher volumes."
Check your voltage source and grounding point. The power supply
of the XD1000/1v2 will operate with charging system
voltages down to 10V. Shutdown problems at higher volume
levels can occur when the charging system voltage (or remote
turn-on voltage) drops below 10V. These dips can be of very
short duration making them extremely difficult to detect
with a common DC voltmeter. To ensure proper voltage,
inspect all wiring and termination points. It may also be
necessary to upgrade the ground wire connecting the battery
to the vehicle's chassis and the power wire connecting the
alternator to the battery. Many vehicles employ small (10
AWG - 6 AWG) wire to ground the battery to the vehicle's
chassis and to connect the alternator to the battery. To prevent
voltage drops, these wires should be upgraded to 4 AWG
when installing amplifier systems with main fuse ratings
above 60A. Grounding problems are the leading cause of
misdiagnosed amplifier "failures."
"My amplifier turns on, but there is no output."
Check the input signal using an AC voltmeter to measure the
voltage from the source unit while an appropriate test tone is
played through the source unit (disconnect the input cables
from the amplifier prior to this test). The frequency used
should be in the range that is to be amplified by the amplifier
(example: 50 Hz for a sub bass application or 1 kHz for a full
range / high-pass application). A steady, sufficient voltage
(between 0.1 and 4.0-volts) should be present at the output of
the signal cables.
Check the output of the amplifier. Using the procedure explained in
the previous check item (after plugging the input cables back
into the amplifier) test for output at the speaker outputs of
the amplifier. Unless you enjoy test tones at high levels, it is
a good idea to remove the speaker wires from the amplifier
while doing this. Turn the volume up approximately
halfway. 5 volt AC or more should be measured at the
speaker outputs. This output level can vary greatly between
amplifiers but it should not be in the millivolt range with
the source unit at half volume. If you are reading sufficient
voltage, check your speaker connections as explained below.
Check to ensure that the speaker wires are making a good
connection with the metal inside the terminal block. The
speaker wire connectors are designed to accept up to 8 AWG
wire. Make sure to strip the wire to allow for a sufficient
connection with the metal inside the terminal block.
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