Dont know if it relates to all 318is or all four pot cars but mine is diffrent colour coded to what has been posted above.
Hope this may help someone out.
1 - Blue
2 - Blue/Black
3 - Nothing
4 - Brown/Purple
5 - Black/Brown
6 - Green/Yellow\
7 - Green
8 - Yellow/White
9 - Black
10-Purple/Green
11-White/Blue
12-Nothing
13-Purple/red large gauge cable
14-Blue/Yellow
15-Black/Green
16-Nothing
17-Nothing
18-Black/Yellow Large gauge cable
19-Nothing
20-Red/yellow
