Thanks BurlThere are two simple test you can do
1)If it is blowing a fuse, unplug the two big plugs from the mpem. If the fuse dosent blow then the MPEM is the short and needs repair. If the fuse still blows the wiring harness has a short. Possibly the carb heater or shift position sensor.
2) if the fuse is not blowing and it dosent work.
Have good fuses and a good battery. Run a wire from the battery positive to fuse 5 the 20 amp fuse. If the dash lights when turned on the wiring harness has a bad splice on the big red wire. You need to find the splice and fix it.
Don't do this if the fuse is blowing as you may cause more damage.
The MPEM does appear to work, as the lights all work, the engine does run, and it does indeed drive.
The problem is, it doesn't shift. It is the semi automatic shift model, with the upshift/downshift button on the handlebar.
When I attempt to shift, the motor reduces rpm as it attempts to shift, but then nothing happens.
My trouble shooting has involved purchasing the MPEM jumper, running the diagnostic, which then indicated that amongst other things, the shift solenoid might be the culprit. The detailed fault states (-Short circuit to battery detected, and -Operating current on the downshift solenoid output has exceeded the overload threshold). Didn't really make sense, but I purchased a new one anyways. Through testing, we have positively determined that it is not the actual solenoid valve. Also through testing we were given the other codes as well, so we are now leaning toward a wiring issue. FYI, the codes are: 4) Downshift Solenoid, 7) Headlight Supply, 8) Accessory Supply, and 9) Reference Supply Output. In the expanded description of the codes, the common thread on the three other codes is short circuit to ground detected. Looking at the wiring diagram from the 2004 model, the wires are not common with these codes.
To be clear, do you know where the two Y splices you mentioned are physically located? I expect we will be taking the whole harness apart, but would be nice to have an idea where to center our search.
Thanks again for the help