Read JBL P 7540 (serv.man3) User Guide / Operation Manual online
7
Symptom
Likely Cause
Solution
No audio
Low/No Remote On Voltage
Check connections; Test turn-on voltage
Speakers are not connected
Check wiring; use VOM/DVM to
or are blown
measure speaker coil resistance
Distorted audio
Input sensitivity is not set properly
See Setting Input Sensitivity on previous page
Audio lacks “punch”
Speakers are wired with wrong polarity
Check polarity of connections;
refer to Applications
refer to Applications
Audio cycles off and on;
A protection circuit is turning the
Verify the following: electrical system is
Amber protection LED
amplifier off and on
between 5 ~ 18 V dc; temperature is not
(JBL badge on top panel)
over 194°F (90°C); no short circuits; speaker
is flashing
loads are not less than 2 ohm (4 ohms in
mono)
mono)
Audio cycles off and on; Amber
GAIN is set too high
Set Input Sensitivity correctly
protection LED (on top panel)
(see previous page)
is flashing
Fuse blows
Incorrect wiring or short circuit
Check connections; refer to Applications
Many different system configurations are
possible using the crossovers and pre-
amp outputs featured in Power Series
amplifiers. If you are considering
expanding you system beyond what is
shown here, please consult your local JBL
installation specialist who is experienced
in designing complex mobile audio
systems.
possible using the crossovers and pre-
amp outputs featured in Power Series
amplifiers. If you are considering
expanding you system beyond what is
shown here, please consult your local JBL
installation specialist who is experienced
in designing complex mobile audio
systems.
Troubleshooting
Use the following guide to identify
symptoms and solve problems. Make
sure the vehicle’s electrical system is
working properly and power is reaching
the amplifier.
symptoms and solve problems. Make
sure the vehicle’s electrical system is
working properly and power is reaching
the amplifier.
Click on the first or last page to see other P 7540 (serv.man3) service manuals if exist.