Wire color designation (Opel Kadett E)

Letters	Color	Letters	Color
BL	Blue	LI	Purple
BR	Brown	RT	Red
HBL	Blue	SW	Black
GE	Yellow	VI	Violet
GN	Green	WS	White
GR	Grey

The first two letters indicate the color of the wire itself, the second two indicate the color of the stripe on the wire. The numbers in the break in the wire route indicate the cross-section of the wire in mm². Fuses are designated on the diagrams by the letter F. For example, F18 indicates fuse #18. The number indicated on the diagram in the frame shows which circuit this circuit is connected to.

(Source is on this resource: www.OPELBOOK.ru)