JBL CS Series, Service Manual

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Features, specifications and appearance are subject to change without notice.
CONTROLS AND SETUP
SYMPTOM LIKELY CAUSE SOLUTION
No audio No voltage at BATT+ Check voltages at
(POWER LEDs or REM terminals, amplifier terminals
are off) or bad or no ground with VOM
connection
No audio Amplifier is Make sure amplifier
(POWER overheated cooling is not blocked
LEDs are on) at mounting location;
verify speaker-system
impedance is within
specified limits
Voltage more than 16V Check vehicle
or less than 8.5V on charging system
BATT+ connection
SYMPTOM LIKELY CAUSE SOLUTION
No audio Voltage less than 9V on Check vehicle
(POWER BATT+ connection charging system
LEDs flash)
DC voltage on Amplifier may need
amplifier output service; see enclosed
warranty card for
service information
Distorted audio Input sensitivity is Check INPUT
not set properly, or LEVEL setting; or
amplifier or source check speaker wires
unit is defective for shorts or grounds
Distorted audio Short circuit in Remove speaker leads
and POWER speaker or wire one at a time to locate
LEDs flash shorted speaker or
wire, then repair
Music lacks Speakers are not Check speaker
“punch” connected properly connections for
proper polarity
SETTING THE
CROSSOVER(S)
Determine your system plans and set
the crossover mode switch accordingly.
If your system design does not include
a subwoofer with the CS50.4, set the
crossover mode to FLAT and skip to
“Setting Input Sensitivity.”
Initially set the crossover frequency
control midway. While listening to music,
adjust the crossover for the least
perceived distortion from the speakers,
allowing them to reproduce as much
bass as possible.
Systems using a separate subwoofer set
the crossover mode to HP (high pass) for
your full-range speakers. Adjust the
crossover frequency to limit bass and
provide increased system volume with
less distortion.
For subwoofers, choose the highest
frequency that removes vocal information
from the sound of the subwoofer.
If using the CS50.4 to drive a subwoofer(s),
set the crossover mode to LP (low pass).
SETTING INPUT
SENSITIVITY
1. Initially turn the INPUT LEVEL control(s)
to minimum (counter clockwise).
2. Reconnect the (–) negative lead to the
vehicle’s battery. Apply power to the
audio system and play a dynamic music
track.
3. On the source unit, increase the volume
control to 3/4 volume. Slowly increase
the INPUT LEVEL control(s) toward three
o’clock until you hear slight distortion
in the music. Then reduce the INPUT
LEVEL slightly until distortion is no
longer heard.
NOTE: After the source unit is on, blue
LEDs (on the top panel) will light, indicating
the amplifier is on. If not, check the wiring,
especially the remote connection from the
source unit. Also refer to “Troubleshooting”
guide below.
TROUBLESHOOTING
3
CS Series 50.4