Steren HER-435 Manual Del Usuario página 24

Breakdown
In this case, turn on all LEDs on both units, however, if some LED
in the "Master" unit has a brighter tone, while the "Remote" is off,
the corresponding pin is in breakdown voltage
Tests examples:
HDMI (A) – HDMI (A) The 4, 5, and 6 pins, are in breakdown voltage.
HDMI (A) – Mini HDMI (C) Los pines 4, 5, and 6 pins, are in breakdown voltage.
Mini HDMI (C) – Mini HDMI (C) The 4, 5, and 6 pins, are in breakdown voltage.
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