400 EXC electrical problems

Hi Everyone, new member here,

I just recently bought an '01 KTM 400 EXC which has an aftermarket supermoto kit installed. However I'm experiencing some electrical issues (all known when I bought the bike)

Here's what works:

-Ignition (I can kick start it and it runs fine)


-Tail/brake lights (rear brake switch only, front brake switch does not work)

-2 separate kill switches (one factory, one from the aftermarket kit)


-Turn signals and hazards do not work

-Horn does not work

-Electric starter does not work

-High/low beam switch apparently does nothing

-Also the light switch (Hazard, parking, ON) is kinda messed up. When you switch to the ON position it kills the engine. Either of the other positions do nothing...the headlight is on all the time.

Today I tested the e-starter by jumping the connection across the starter relay and it turns over no problem. Checked the fuses, none of them are blown. I also followed the wiring diagram and everything seems to be in order as far as i can tell. I took most of the connections apart and cleaned them with electrical contact cleaner...some of the connections looked fairly corroded. I disconnected the voltage rectifier while the bike was running per the KTM repair manual, and still the same issues are there. I installed a brand new battery, as the old one was reading 0.9V on the voltmeter and wouldn't take a charge. I'm starting to get frustrated here and running out of options short of replacing the all relays, the voltage rectifier and CDI box. Any suggestions? I apologize in advance if this same issue may have been covered in the past. I searched but could not find a remedy. Thank you very much for anyone that may have some input!

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