NAD C-275-BEE- in protection amber mode (EM78P153SP controller)

Hi, everybody !

I need some help to understand why the unit is in amber protection mode (not red protection mode).

If soft clipping activated -> start flashing soft clipping LED.

Outputs checked as diode, seem ok all of them.

Amber protection mode also if left channel & right channel disconnected (all 3 plugs - main voltages - input - subsidiary voltages)


Voltages on controller:
EM78P153SP
Pin-08 P62/TCC signal enable-out 0_
Pin-09 P61 switch_enable-out 0_
Pin-10 P60/INT thermal-in, 5 V = ok 5.5
Pin-11 Vss Vss 0_
Pin-12 P53 trigger-in 4.8
Pin-13 P52 signal-in 4.8
Pin-14 P51 protect 0_ (0 in protection mode ?)

Pin-07 P63/RST Reset 4.4
Pin-06 P64/OSCO ON/OFF-in 4.4
Pin-05 P65/OSCI trigger enable-out 0_
Pin-04 Vdd Vdd 4.4
Pin-03 P66 amber 0_
Pin-02 P67 MUTE-out 4.4
Pin-01 P50 STD_BY-out ? 4.4

service-Nad-C-275-BEE-Service-Manual_08-MB SCH-01.jpg
service-Nad-C-275-BEE-Service-Manual_10-Display SCH-01.jpg
service-Nad-C-275-BEE-Service-Manual_10-Std-BY SCH-01.jpg