Denon AVR-591 Service Manual page 19

2.3. Clearing the protection history
There are two ways to clear the protection history, as described below.
(1) Start up the error (protection display) mode, display the error, then press and hold in the "ENTER" button for 3 seconds.
FLD
: T H E R M A L T H E
FLD
P R T : C L E A R
FLD
N O
(2) Initialize. (Refer to "Initializing AV SURROUND RECEIVER" 5 page.)
b If you want to save a backup, use the method in 2.3.(1) above.
Warning indication by the POWER LED
If the power is turned off when a protection incident has been detected, the POWER LED (red) flashes as a warning
according to the conditions in which the protection incident occurred.
(1) ASO/DC PROTECTION : Flashes in cycles of 0.5 seconds (0.25 seconds lit, 0.25 seconds off)
(2) THERMAL PROTECTION : Flashes in cycles of 2 seconds (1 second lit, 1 second off)
Press and hold in the "ENTER" button for 3 seconds.
The above is displayed and the protection history is cleared.
P R O T E C T
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