Hi, Mattias it should be noted that the reasons your FI light stays on constantly or flashes and your bike will or will not start and may turn over or may not and run great or sputter, these conditions will vary from bike to bike depending on the year, make, and model and you should always refer to your owners/service manual for proper diagnostic procedures. It should also be noted that any type of prior work done to the bike or an abnormal event occurrence IE: adding accessories, electrical curiosity/adventures, laying the bike down/crashes, rain storms/bike washings just before FI light issues started can be significant hints/aids into tracking down the gremlin, also carry the appropriate jumper wire to access fault codes to reduce the risk of being stranded or towed. The newer the bike the more sensitive the ECM becomes and will not let the bike start when aftermarket accessories have been installed without being reprogrammed. That being said the usual suspects are:
1. Faulty Fuel Pump, fuse or system relay switch.
2. Battery starting to fail due to old age/damage, perform a load test.
3. A discharged battery, check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
4. Faulty safety switches/sensors: run/off, ignition, clutch lever, neutral, side stand, tip over, fuel, and or their connections.
5. Broken wire or worn insulation exposing wire to a ground situation especially inside wire harness at tight bends around fairing brackets, under dash panels, under fuel tanks over cylinder heads, etc. Many harnesses are open on the ends that will allow water to enter and accumulate at v-bends.
Dielectric grease and contact cleaner are your best friends for wire/cable/harness connectors, look for corroded, broken, or loose pins/sockets.
6. Installation of aftermarket accessories ie. exhaust systems, mufflers, air cleaners, fuel tuners, electrical component, etc.
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