Connect2 AUX Adapter

maxhoo2118 wrote:And also on the rear of the head unit there are three sockets, two of which are occupied so I'm guessing there the Power and Speakers, but whats the third for? The third seems to be longer than the other two

https://pinoutsguide.com/CarAudio/car_audio_iso_pinout.shtml wrote:Car audio ISO connector A pinout
Pin
Number Pin
Name Description
1 A1 SCV - speed-dependent volume control. This pin is used in some radio equipment to automatically boost up the volume. It needs the output from the speed sensor. Note: If the speedometer stops working when the radio is connected, then the pin is probably grounded because radio probably uses this pin for another function, except for GALA.
2 A2 Mute from Cell-Phone. This pin is used to silence the audio cd, earthed by some other external components such as a mobile phone that is connected to the radio.
3 A3 the reversing light switch. Satellite navigation uses this signal, the GALA signal (pin 1) and an internal laser gyroscope to calculate position in the absence of satellite signals. +12 V input on the radio with the ignition switched on the ignition and the car is in gear to move backwards.
4 A4 Memory Power (12V direct from Battery). Connects the radio directly to the battery.
5 A5 Power for Electric Antenna. Output from the stereo +12 V (maximum 150 - 300mA) power supply for automatic or electronic antennas.
6 A6 Dial-light illumination (car side light circuit). +12 V input on the car when the lights are on. For some it actually illuminates the radio display - the others can dim the lights. If the dashboard of your car has a light control function, this pin should be connected in order to regulate the brightness. The wire from lighting a cigarette lighter can be used for the same purposes.
7 A7 +12V Main Power (Switched via Ignition key). +12 V with the ignition key is in the ACC or ON position.
8 A8 Ground (Chassis)



Car audio ISO connector B pinout

Connector B is used only for the speakers. Which wire goes to which speaker can be easily determined with a battery of 1.5 V. Speaker will click and you will see the diaphragm move forward or backward. Speakers must be properly phased (note the + and - half on the speaker), because otherwise you will have weak bass. Wire with a stripe usually goes to + pole of speaker.
Pin
Number Pin
Name Description
1 B1 Right Rear +
2 B2 Right Rear -
3 B3 Right Front +
4 B4 Right Front -
5 B5 Left Front +
6 B6 Left Front -
7 B7 Left Rear +
8 B8 Left Rear -

Car audio ISO connector C pinout

Connector C are consist of 3 separate connectors that are tied together. It is not always present, sometimes only a part.
Pin
Number Pin
Name Description
1 C1 Line out left rear
2 C2 Line out right rear
3 C3 Line out ground
4 C4 Line out front left
5 C5 Line out front right
6 C6 +12v switched - maximum 150mA
7 C7 RXD
8 C8 TXD
9 C9 Chassis ground
10 C10 +12v switched - maximum 150mA
11 C11 Remote control in
12 C12 Remote control ground
13 C13 CDC data in (bus)
14 C14 CDC data out
15 C15 CDC +12v permanent
16 C16 CDC +12v switched - maximum 300mA (+A)
17 C17 CDC data ground (+U)
18 C18 CDC audio frequency ground
19 C19 CDC audio frequency left
20 C20 CDC audio frequency right