JBL GTO Series 601.1, Service Manual, Page: 7 / 28

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INSTALLATION AND SETUP
To Neon
Power
Supply
To Neon
Power
Supply
Figure 13. Installing neon tubes in a JBL GTO amplifier.
TROUBLESHOOTING
SYMPTOM LIKELY CAUSE SOLUTION
No audio No voltage at BATT+ Check voltages at
(POWER LED or REM terminals, amplifier terminals
is off) or bad or no ground with VOM
connection
No audio DC voltage on Amplifier may need
(PROTECT LED amplifier output service; see enclosed
flashes every warranty card for
4 seconds) service information
No audio Amplifier is Make sure amplifier
(PROTECT overheated cooling is not blocked
LED is on) at mounting location;
verify speaker system
impedance is within
specified limits (see
“Specifications” on
the next page)
No audio Voltage less than 9V on Check vehicle
(PROTECT BATT+ connection charging system for
and POWER defective voltage
LEDs flash) regulator
SYMPTOM LIKELY CAUSE SOLUTION
No audio Voltage more than 16V Check vehicle
(PROTECT or less than 8.5V on charging system for
LED is on) BATT+ connection defective voltage
regulator
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 PROTECT speaker or wire one at a time to locate
LED flashes shorted speaker or
wire, then repair
Music lacks Speakers are not Check speaker
“punch” connected properly connections for
proper polarity
GTO Amp OM 2/3/04 3:54 PM Page 7
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