Wiring schematics & diagrams
Disclaimer & warning:
Be careful when using these diagrams. The harness changed bit by bit over the years. You can use the schematic to find the wire you're looking for, but don't assume that it's correct. Test any wire for function before splicing into/diverting/eliminating it. For instance, the wiring diagram in the 2002 Service Manual Supplement isn't even 100% correct for the '02 bike, and the '04 is different yet.
Tip: Yellow and black wire is ground throughout the bike.
EX250 Wiring Schematic (full color - large & detailed)
Old Wiring Schematic (B&W)
Start & Ignition Schematic (full color)
Start & Ignition Troubleshoot Schematic (full color)
Assorted schematics by Anna's Dad
Anna's Dad is pretty good with CAD software, and he has drawn up a number of useful diagrams and schematics for the 250F. The full-color ones listed above are his.
He has set up a site where he can post his drawings and any updates he makes to them. Follow the link below to the table of contents:
As of September 2010, the following drawings were listed: