AUX AUDIO IN L and AUX AUDIO IN R feature as connections on some universal android head units. But what to use them for and are they necessary to make it work? Or maybe the aux audio is not working and you need to know if the AUX AUDIO connections have been made correctly to the android stereo.
Breakdown of AUX AUDIO IN L 1
AUX is for auxiliary, the alternative input for connecting audio device by a cable.
AUDIO is for the sound only. Not to be used for video signals which are carried by this wire.
IN identifies an input, so you connect the output of an audio device to the INPUT of the android headunit connection.
L or R is label to identify the LEFT channel or RIGHT channel for stereo audio. The L+R channels are common on all stereos.
1 or 2 A number may be present to differentiate between the different L+R pairs if there is more than one available.
AUX_AUDIO_IN_L_1 Is the first pair designation of the left channel for audio input of the auxiliary circuit.
This connector may be a white RCA socket, either built into the unit or on a flying lead.
For a stereo image, the corresponding AUX_AUDIO_IN_R_1 should be connected to the same source, the AUX_AUDIO_IN_R_1 is usually a red colour RCA socket on the board or as a flying lead.
Problems with AUX_AUDIO_IN
You need to select ‘AUX INPUT’ on the headunit with the app to engage the aux input option.
If you get aux sound from only one side of the speakers, but other audio (like radio) is ok, then you may not have a good connection to either AUX_AUDIO_IN_L or AUX_AUDIO_IN_R, ensure the correct plugs are in the right sockets. You can swap the plugs (usually white and red) for AUX_AUDIO_IN_L and AUX_AUDIO_IN_R over to test if the speakers also swap over or the sound stays quiet on the same side.
If your music swaps over to the other side then suspect your source balance and the lead is pushed fully home into the phone.
If your music stays on the same side despite swapping the AUX_AUDIO_IN connections over, suspect the head unit, check the balance fader or EQ app for L and R sound balance.
Typical AUX_AUDIO_IN connectors
Typical AUX_AUDIO_IN is an RCA socket, either RED for RIGHT CHANNEL or WHITE for LEFT CHANNEL. The aux connection is often made from a phone or MP3 player via the 3.5mm jack plug. There are standard 3.5mm jack to dual RCA Phono plug leads (eBay), designed for this exact AUX IN job.