Ericsson Accessory Connector Pin-outs 1 Audio input 2 +5V=External Power, 0V=Battery 3 PA Speaker control 4 Audio Ground 5 Audio Output 6 Power-on indicator 7 Charger control 8 Digital/DC GND 9 0V=normal,+5V=test, +12V=test+flash 10 hangup signal 11 TTL serial input 12 TTL serial output 13 Power Toggle (hold low 1 second) 14 DC Power supply IN