OK, this should be my final update on this. I have completed the install of my headlight relay delay circuit.
To recap: when you install a set of HID H4 headlights, because the stock FJR ECU turns the headlights on immediately after the engine starts up, and the starting process may drain down the battery a bit, some folks have noticed that their Xenon capsules are not 100% reliably firing up. The idea here is to wait for a while after the engine starts to allow the alternator to ramp up a little before attempting to turn on the lights.
I designed a little time delay circuit which can be put in series between the ECU and the #1 headlight relay to accomplish that goal. In my prototype circuit I required 3 wires: a +12V (switched) signal supply, the signal from the headlight relay and the control signal from the ECU. After determining that I'd really like to install this circuit under the seat (near the ECU) rather than hidden inaccessibly up in the nose cowling, I reworked the circuit to a 2-wire input circuit such that the Vcc is common to the signal from the relay. This definitely simplifies installation. (I have modified the schematic above to reflect this change).
In my first board (picture above), getting the 3 external signals made the board pretty busy. After redesigning the board for just the two inputs, it simplified the board greatly. Also, in the first iteration I attempted to seal the components with an acrylic conformal coating and then pot them in a silicone compound. It was messy, and a heavy little brick.
Iteration 2, after the circuit changes, I merely coated the board well in acrylic conformal coating and dropped it into a small project box bought at Rat shack. Here you see the simplified board components, in the small project box. The milky looking coating of the board is the acrylic conformal coating before fully cured.
I placed this circuit in series with the headlight relay ground signal coming the ECU, which is the Yellow w/ black tracer wire in the ECU connector. Rather than cutting into the precious FJR wiring harness, I just unlocked the ECU connector pins, as is detailed in the
Barbarian jumper mod instructions, and pushed the yellow/ black wire out of the connector. I then stripped a section of wire and shoved as many strands as I could into the small orifice of the female ECU pin, wrapping the remaining strands around the exterior of the pin. After installing shrink-tube around this connection it looks to be a fairly sturdy connection. And reversible. (no damage was done to this FJR for this mod).
After adding some molex connectors to the wires and sealing up the project box with silicone sealing compound I think this thing should be able to brave the elements. I tucked the sealed box in under the seat (along with my AVCC) so if it should fail I will easily be able to replace the circuit board with a molex jumper I have already made up and hanging from the box.
Sorry that this is not a great step by step procedure. I'm not sure how many folks will get any value out of it, so am hesitant to invest the time to do so. Maybe if a bunch more people have a need I'll collect all the info and pictures in a single document for posterity.