Hi @Frederic
Many thanks for your answer.
1) With the multimeter I was able to find the battery cable (red/black), illumination (green/black) and ignition (thick blue).
Tried to find the ground wire using the multimeter feature for wire continuity but no success.
Also tried the remain cables (in pairs) to try to identify the speakers with the same continuity feature. no chance...
2) Indeed, I got that this color code are the default for the majority of vehicles but mine only has the white, white/black; green, green/black; yellow, yellow/back; red, red/black and beige, beige/black...
This vehicle has been bough in Dubai for export.
You can have its characteristics through Partsouq site.