JL Audio J2250.1 Car Amplifier User Manual


 
15
“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 0.2 and 8.0-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 half
way. 5V 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.