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Relay Box Layout

Electrical Box Contents

By: Paul Glaves
March 1999

I have sorted out the components in my K75 electric box. They do not match the chart in the Clymer K bike manual which appears to be totally flakey. They do match several photos in the Haynes manual and have been field verified. Haynes does not have a complete chart.

I have 9 components in the box – two are (optional).

Starting left to right across the front:

1. Small Black – Fuel Pump Relay
2. Blue Bosch 30A – (Optional) Low Beam Driving Light Relay
3. Blue Bosch 30A – Headlight/Load Shed Relay
4. Blue Bosch 30A – Horn Relay

Center Row left to right

5. Black Rectangular – Bulb Monitoring Unit
6. Blue Bosch 30A – (Optional) High Beam Driving Light
7. White Rectangular – Temperature Control Monitor – Fan Relay

Back Row left and right

8. Large Green Rectangular – Turn Signal/Flasher Unit
9. Black Rectangular with bolt on wires – Starter Relay

Note that 2, 3, 4, and 6 are identical 4 pin Bosch 30A relays. When I added the optional factory driving light kit I could have reversed the sockets for 2 and 6. The sockets came as part of the kit and just plugged into an existing plug.

Assuming they bolted the relay sockets in the same as on mine, your K100 should be the same. It looks possible to reverse the sockets for the Headlight and Horn in the right front corner but that’s about all that could be different. For what its worth Clymer showed the black fuel pump relay up in the right front corner – mine isn’t there!

Mine are getting numbered stickers with a number key in the lid, but now that I’ve finished doing this I might remember anyway.

Pictorial Recap:


Fuel Pump     Driving Light     Headlight     Horn
  Relay           Relay           Relay       Relay

Bulb Monitor              Driving Light        Fan
    Unit                      Relay           Relay

Turn Signal/Flasher                           Starter
      Relay                                    Relay


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