Topic: CB400F Electrical

[CB400Finhawaii]

Aloha,

Made good progress on my CB400F.  So far I have:
- Replaced the master cylinder and caliper
- Replaced fork seals
- Install new tires, tubes, rim liners
- Rebuilt carbs
- Replaced the chain, front and rear sprockets
- Repaired the seat foam and recovered the seat
- Removed rust and sealed the tank.  It is going to be professionally painted as I can't get paint shipped to Hawaii to DIY it
- Replaced throttle cables and clutch cable
- Replaced handle bar switches

Now the hard part for me is the electrical system

There were several wires that were cut.  I think they have all been fixed.

I installed a new battery and the only things that worked were the horn, neutral light and the front blinkers (they didn't flash and I assume it is because the rear blinker light wires were cut at the time).   Nothing else worked.  I pulled the fuses to check if they were good, which they were.  However when I replaced the fuses, nothing worked.

Where should I begin?  Can anyone point me a direction to start? 

Are there any good videos online that can step me through diagnosing and fixing my electrical system?  I know Common Motor Collective has some good videos and will watch them all.  Are there any other sites anyone recommends? 

Mahalo,

Mike

[BenelliSEI]

Start with the basics. Find a colour coded wiring diagram for your exact model and print a colour copy. Pull the headlight out and see if all the wires are connected in there. It’s where the seperate pieces of the harness connect. They are generally all plugged together with the colours matching. Take some pictures and post what you find.

Next see if you have power to the key switch. If the neutral light comes on with the key, sounds like you do. There should be power to the coils when the key is on. Test the black  wires with a test light. Power at the coils? It comes through the kill switch. If not, find those wires in the headlight bucket and see if the switch is faulty. Power going to the switch? Coming back when it is in the run position? Connected to coil feeds? Post what you find.

Your turn signals might not flash if the rear lamps are not  connected. The flasher needs the full load to heat up and open/close. The power wires for the turn signals are light blue on one side of your bike and orange for the other. The green is for ground everywhere. Hook up the rears. Do they flash now? Good luck!

[BenelliSEI]

Find out if you are close to “MauiK3”. Be a handy guy to invite by for a beer and some sound advice!

[newday777]

Did you test the fuses with a volt meter or test light?
Did you wiggle the key in the on position?(ignition switch can go bad, bad contacts if key ring had multiple keys on it and bounce/rattle going down the road)
I just had to replace the ignition switch on a 750 because of it having bad contacts.

[CB400Finhawaii]

Thanks for the info.

[CB400Finhawaii]

I tested with a multimeter.  I did not wiggle the key, but will try it. 

Thanks all for the help.

[CB400Finhawaii]

The seat cover was torn and foam cracked.  I used silicon caulk to fill the cracks in the seat.  I figured that consistency was close enough to the foam that it would work well and that it would work better than trying to glue pieces of foam into the cracks.  The caulk went in easily and was easy to smooth.