Bose FreeSpace Business E4 II Series Service Manual page 82

Amplifier fault
The AMP OUTPUT LEDs work in pairs (1
and 2, 3 and 4) and indicate the operating
status of the four amplifier output channels.
AMP OUTPUTS
SYSTEM
STATUS
1 2 3 4
AUDIO SOURCES
DIRECT
INPUT
1 2 3 4
When an amplifier fault occurs, the amplifier
mutes its outputs and indicates an error.
After a short period of time the amplifier will
try to operate again. If the fault condition
persists, the amplifier will attempt to restart
six times, after which it will remain muted.
Amplifier faults are typically caused by a
shorted loudspeaker line, an overdriven
amplifier, or a saturated output transformer.
• To check for a shorted loudspeaker line,
remove the loudspeaker connection from the
amplifier channel. If this resolves the prob-
lem, locate and correct the shorted loud-
speaker line.
• To make sure that you are not overdriving
the E4 Series II output, change to a different
source. If the problem no longer exists, use
the Installer™ software to reduce the input
level of the original source that was
overdriving the output.
• To make sure an output transformer is not
being saturated, check to see if the correct
loudspeaker EQ setting is selected.
If none of these actions solve the problem,
read the instructions in the following flow
chart or check the error log using the In-
staller software.
TROUBLESHOOTING
Check for
• Shorted wiring
• Overdriven amplifier
(reduce output gain)
• Transformer saturation
STANDBY
• Entry in Installer™ soft-
ware error log
AMP OUTPUT
indicators are red
Has the E4 unit Yes
shut down during
operation?
No
Is SYSTEM
STATUS indicator
green?
Yes
Does the Installer™
software Error Log list
any amplifier
faults?
No
Perform test procedures.
If unit passes, return to customer.
82
• Check the number of loudspeak-
ers connected to the E4 unit.
Verify that the total sum of loud-
speaker taps connected to the
E4 unit does not exceed 400W.
• Verify that there are no shorts on
the speaker output lines.
• Switch POWER to OFF.
• Disconnect the load and switch
No
POWER to ON.
• Verify that there are no shorts on
the speaker output lines.
Yes
See amplifier fault troubleshooting
section for course of action.