FI fault light and weird electrics number - Wrist Twisters
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post #1 of 7 Old 07-30-2019, 06:01 PM Thread Starter
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FI fault light and weird electrics number

Hey all, I was putting some LEDs on the bike, hoping to get a little more sideways throw. Install went fine, lights worked fine, bike ran. Cleaned up the wires a bit, bike started throwing the FI light and refusing to start or prime the fuel pump. Had this before when the bike thought it was being stolen, so checked the pink wire under the seat. Voltage of 8.7-8.8, which seems weirdly low. Battery is charged as per the charger. Checked the wires coming out of the ignition; I have the green wire, one red, one black, and one white and black. Red and black read 12.something, but the white and black wire reads the same 8.7 or 8.8. Is this the diode being blown? One of the fuses on the LEDs, after I took them off, was blown, or at least looked blown. Replacing that fuse didn't change things, and from what I can tell the fuses underneath the seat look fine. Ground wire from the tank has been fine and I didn't interfere with it to get the lights on. Any ideas?

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post #2 of 7 Old 07-30-2019, 06:25 PM Thread Starter
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Took the cover off the ignition and measured from the source, as it were. Voltage going into the diode is 12.7, only 8.7 coming out. So partially failed open, dropping the voltage too far? Anyone got a good source for these stupid things?

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post #3 of 7 Old 07-30-2019, 11:13 PM
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Good luck with this. I'm a novice when it comes to chasing electrical gremlins.Only just got myself a multimeter.
Am a keen student so be good if a knowledgeable sparky chimed in.
I do remember reading a thread here somewhere on that ignition diode.

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post #4 of 7 Old 07-31-2019, 12:00 AM
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Calling Rob Tharlson..

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post #5 of 7 Old 08-03-2019, 11:51 AM
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Most all of these weird electrical issues that start all of a sudden usually end up being a bad battery. I would start by taking the battery to an auto parts store and have it load tested. Just because the battery is charged and reads 12V, it could still not be able to start the bike.
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post #6 of 7 Old 08-07-2019, 09:17 AM Thread Starter
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Battery is reading 13 and some across the terminals, when the bike is off and when it's on. The diode was suspect so I took it out, and I'm measuring the voltage into the pink wire, #19 on the gray connector, with the meter. I couldn't find the exact diode Honda uses, of course, so I grabbed some that are kinda close in value. Rob said elsewhere that the voltage into that wire needs to be between "10.5 and 11 volts," so it's a pretty pissy little thing. Off to the electronics shop.

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post #7 of 7 Old 08-08-2019, 11:50 PM
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Quote:
Originally Posted by draco880 View Post
Hey all, I was putting some LEDs on the bike, hoping to get a little more sideways throw. Install went fine, lights worked fine, bike ran. Cleaned up the wires a bit, bike started throwing the FI light and refusing to start or prime the fuel pump. Had this before when the bike thought it was being stolen, so checked the pink wire under the seat. Voltage of 8.7-8.8, which seems weirdly low. Battery is charged as per the charger. Checked the wires coming out of the ignition; I have the green wire, one red, one black, and one white and black. Red and black read 12.something, but the white and black wire reads the same 8.7 or 8.8. Is this the diode being blown? One of the fuses on the LEDs, after I took them off, was blown, or at least looked blown. Replacing that fuse didn't change things, and from what I can tell the fuses underneath the seat look fine. Ground wire from the tank has been fine and I didn't interfere with it to get the lights on. Any ideas?

Er, how *exactly* did you wire these up? Did you run fresh wire from the battery to the lights and control them via a relay/switch or what?

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