Contrary to popular belief you do not need a reset “tool” to reset the service indicator and inspection lights on your dash. All you need is a simple piece of wire (strip both ends):
This wire will act as a jumper wire between two terminals. Some people suggest using a wire with a fuse in the middle, but mainly this is only to protect you from jumping the incorrect wires. If you do this correctly shouldn’t be a need for a fused wire, but its upto you.
Location of diagnostic plugs:
Or you could do it with needle nose pliers like this:
Take this piece of wire and jump these two pins.
Determine orientation of pins you need to jump by the direction of the “pac-man”. This style is the later diagnostic plug style (most common).
Early E30’s came with plugs like below.
After Jumping the wires put the car into accessory mode (one click past radio mode, but not all the way to start the car). After 3-4 seconds you will reset service light indicator. If you wait 6-7 seconds you will also reset the inspection light.