Sir HikaruGunner . . . . . (Japonie-Englee ?)
Here is a mark up diagram of what the different connectors pins are routed to within your main unit..
With one variance . . . . . of your plug colors, being so pale that the Orange appears more of a pale Orange / Yellow blend, with the Black being true Black and the Green being pale also.
If you used an MP4 audio test source, that would be dependent upon it having a female output connector . . . . or gender adapter.
Since you have nothing but a Multimeter (analog ? ) / DVM, lets just use a NEANDERTHAL test procedure.
Either hook up all speakers or walk I speaker between the different testing inputs as you do them.
With the possible exception of the RED /BLACK wire pair which I assume to have been un soldered from the units woofer speaker, where you might reconnect using jumper wires or extra wire pair lengths.
You power up and . . . .say . . . .opt to test the Green connector first, with it being all speakered up.
Check that your Multimeter (analog ?) /DVM is in its OHM or DIODE test mode.
Run the remote volume control to max and take one /either ohmmeter test lead and finger /grip hold it to the innermost ground connection and then use the other ohmmeter probe and just do a very quick " blip" connect to the proper ring that you have a speaker monitoring. It should give a static sound burst if the amp is amping for that speaker.
Proceed thru all of the other 4 speaker output options.
Inform us accordingly . . . . . also look at your meter and if being an el-cheapo, they might have also put a capacitance test capability on it . . .tell us if so.
DIAGRAM - I - COM . . . . .
73's de Edd . . . . .
I may not be totally perfect, but there are certain parts of me that are excellent.
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