The wiring diagram of the Suzuki is not correct. Also, you are inverting the polarity of the speaker. That's no big deal if you put them inverted (they will be in relative phase), but things can get complicated if you put 4 speaker. Most probably they will end inverted. Based on my Suzuki Jimny, double checked by me, this is the correct wiring:
Read this as follows: Channel (cable color in a standard ISO connection) -> Cable color in the Jimny
The wiring diagram of the…
The wiring diagram of the Suzuki is not correct. Also, you are inverting the polarity of the speaker. That's no big deal if you put them inverted (they will be in relative phase), but things can get complicated if you put 4 speaker. Most probably they will end inverted. Based on my Suzuki Jimny, double checked by me, this is the correct wiring:
Read this as follows: Channel (cable color in a standard ISO connection) -> Cable color in the Jimny
Rear Right + (Violet) ---> Green
Rear Right - (Violet-Black) ---> Green-Black
-----------------------------------------------------------------------
Front Right + (Grey) ---> Blue
Front Right - (Grey-Black) ---> Blue-Black
-----------------------------------------------------------------------
Front Left + (White) ---> Red-Green
Front Left - (White-Black) ---> Black-Red
-----------------------------------------------------------------------
Rear Left + (Green) ---> Grey
Rear Left - (Green-Black) ---> Grey-Black
There are also some adapters sold ready, and common for Suzuki / Alfa / Fiat / Lancia / Ford / Nissan / Vauxhall...
Also, I recommend putting some quality plastic washer between the speaker and the car chassis to prevent vibration.
In any case, let me give you a big thanks for your fantastic explanation!.