BSA C15 no spark

[jmac]

Hello All

Would welcome assistance with my lack of spark on my C15.

Lights are fully operational
Earths are good ( additional earth  added from engine to frame )
Coil is good ( ohms checked OK)
Lead and plug are  good (ohms checked)
timing checked ok
points checked ok
Battery is good
New plug

I am getting no power to points wire,
I used a jump lead from battery to coil which resulted in power being achieved at points lead

I conclude that the issue must be either the ignition switch or a fault in the wiring to or from the switch

Next job is to confirm I am receiving power through the brown and white cable from the battery /ammeter to ignition switch 12a
And out via the black and white cable 15a 

Appreciate if someone could confirm I am going in the right direction.

Advice welcomed

many thanks

Jim

[DAVE BRADY]

Hi Jim,

If you have the standard ign. switch make sure that it is fully pushed together.  They can work loose and result in no spark.  It happened to me many years ago on a B40.

Dave. 

[jmac]

Dave
Cheers for the tip, will check it out

Jim

[rhyatt]

Start with a multimeter set on volts DC scale.
Are you + or - earth , whichever you are put the black or red onto earth with a Croc clip.
Then the other should have a probe and start your diagnostic steps by Verifying that you have 12v at the battery.
Then check 12v at any fuse , ensure the points are open and check for 12v at the moving point,(ign on of course), yes  no?
Yes   great your primary side is fine.
No, check at coil , into the coil and out the other side to the points.