Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: Coppertop1234 on January 17, 2026, 05:36:55 PM

Title: Cb400/4 No power to points
Post by: Coppertop1234 on January 17, 2026, 05:36:55 PM

Hi all been away for a while from the forum
wow last post was 2018 time flies
but the biking bug never dies.
Just playing with a 400/4 and no power to points

Powers up and turns over fine

Checked wiring connectors all seem ok
Replaced points condenser - same issue
kill switch seems ok
possible zenner diode fault?

advice appreciated

Title: Re: Cb400/4 No power to points
Post by: Oddjob on January 17, 2026, 05:50:38 PM

Power to coils on the black/white wire?

Title: Re: Cb400/4 No power to points
Post by: Coppertop1234 on January 17, 2026, 05:53:38 PM

will check them out tomorrow cheers

Title: Re: Cb400/4 No power to points
Post by: Coppertop1234 on January 17, 2026, 06:15:04 PM

No power to coils
New battery fitted
??

Title: Re: Cb400/4 No power to points
Post by: McCabe-Thiele (Ted) on January 17, 2026, 07:06:54 PM

I would start by checking the voltage from the ignition switch and work my way using the wiring diagram following the ignition feed  wire all the way to the coils.

Title: Re: Cb400/4 No power to points
Post by: Oddjob on January 17, 2026, 07:32:32 PM

Coils are powered through the kill switch. Open the headlight and see if the switch has power and if so it's coming out of the black/white wire in the headlight. If not the switch is most likely dirty, simple to clean if it is. You could jump the kill switch by jumping a black wire into the black/white wire and see if it fires up, ignition switch on of course.