When it came time to install the driving light relay and AutoSwitch, I began to look for the most convenient location where they would be easily accessed and out of the elements. The choice was simple; the BMW Fuse and Relay Box and for more reasons than those just mentioned. Read on!
The AutoSwitch required two connections where tapping into the BMW factory wiring was necessary. Tapping into factory wiring isn't my style, so I came up with a solution. Instead of tapping into the turn signal cancel wire somewhere in the wire harness, why not perform a non-destructive tap at the BMW Turn Signal Relay within the BMW Fuse & Relay box. The switched power for the AutoSwitch is discussed further down.
After removing the BMW Turn Signal Relay from the fuse box (talk about an over engineered connector), I removed the cover from the relay.
The 4th pin from the left, top row, is where I tapped into. The wire was then looped through a groove in the base plate after the thin plastic was cut out...
Molex connectors were used so that the AutoSwitch could more easily be replaced in case of failure. Gold plated pins were crimped and the wire ends where they protrude were soldered for a long lasting, trouble free electrical connection.
Once the relay cover was replaced, the completed BMW Turn Signal Relay looked like this...
The modified AutoSwitch...
Wiring from top to bottom:
Orange wire: this wire connects to the wire exiting the BMW Turn Signal Relay,
Black wire pair: this wire pair connects to the AutoSwitch LED,
Black wire (covered in rubberized heat shrink): this wire connects to the ground bus on my Blue Sea Systems Fuse Block
Violet wire: this wire connects to the driving light relay coil,
Red wire (covered in rubberized heat shrink): this wire connects to switched power in the BMW Fuse & Relay Box.
The AutoSwitch LED was installed in the right side windshield mount. Note: the wire covered in rubberized heat shrink fit nicely in the channel of the instrument panel. It was tucked under the instrument panel and then tie-wrapped to a factory harness to keep the wire snug...
The BMW Fuse & Relay Box with the Hella FF50 driving light relay above the row of fuses (blue) and the AutoSwitch to the right of the row of fuses. Both are held in place with 3M Dual Lock. The BMW Turn Signal Relay is above the red fuse puller...
Not easily visible is the switched power wire from the AutoSwitch that is connected to the fused side (back of the bike) of fuse #8 (counting from the left). This was done by stripping about 1/2" from the switched power wire of the AutoSwitch. After the fuse was removed, the wire strands of the switched power wire of the AutoSwitch were fanned out, then placed across the fuse socket and the fuse pressed in to make the contact.
Any wiring exiting the BMW Fuse & Relay Box does so via the rubber grommet at the front left. There are two smaller holes where the rubber can be punched out to route additional wires (the main harness feeds through the larger center hole). The grommet can be removed by splitting the BMW Fuse & Relay Box.
Wiring exiting the BMW Fuse & Relay Box are:
- main power wire to the driving lights,
- main power wire to the driving light relay from the auxilliary fuse block,
- main ground wire to the driving light relay from my auxilliary fuse block,
- ground wire to the AutoSwitch from my auxilliary fuse block,
- LED wire pair from the AutoSwitch to the instrument panel.
All other wiring connections (Molex) between the AutoSwitch, Hella relay socket and BMW Turn Signal Relay are nicely housed within the BMW Fuse & Relay Box.
I hope this provides some ideas to anyone installing driving lights and using the AutoSwitch to activate them.