BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
JRC Engineering dealers
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons, "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Member Spotlight
Kerry W
Kerry W
Middle East,
Posts: 1,225
Joined: February 2012
Show All Member Profiles 
Shout Box
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Who's Online Now
40 registered members (Andy Higham), 306 guests, and 398 spiders.
Key: Admin, Global Mod, Mod
Newest Members
IDG1, pemdoc65, creativecroc, gregneal, Chris Marsland
10170 Registered Users
Top Posters(30 Days)
Lannis 99
Stuart 83
reverb 82
NickL 73
koan58 56
Popular Topics(Views)
549,701 mail-order LSR
Forum Statistics
Forums34
Topics66,547
Posts645,114
Members10,170
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate Thread
Testing Norton Commando MKIII headlight switches #662765
08/03/16 2:33 pm
08/03/16 2:33 pm
Joined: Nov 2015
Posts: 29
Penna
D
Dnaj11 Offline OP
BritBike Forum member
Dnaj11  Offline OP
BritBike Forum member
D
Joined: Nov 2015
Posts: 29
Penna
I've got a 75 Norton MKIII which had a leaking master cylinder. I've rebuilt the master cylinder but had to take apart and clean the switches on that side which had become contaminated with brake fluid and crud. I took care not to loose the flat tabs and springs inside the plastic switches and believe I did put it together correctly. Unfortunately, I did not test to see if they worked before I started this and the bike has not been run in years. Is there a way to test the switch for the headlight. I'm not sure which wire should have voltage in the various switch positions. I'd like to rule out all other possibilities before taking the small switches apart again. They are not fun to get together with old fingers like mine. Thank you.

Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Re: Testing Norton Commando MKIII headlight switches [Re: Dnaj11] #662767
08/03/16 2:52 pm
08/03/16 2:52 pm
Joined: Mar 2006
Posts: 3,553
Norfolk, UK
L.A.B. Online content
BritBike Forum member
L.A.B.  Online Content
BritBike Forum member
Joined: Mar 2006
Posts: 3,553
Norfolk, UK
Originally Posted By Dnaj11
Unfortunately, I did not test to see if they worked before I started this and the bike has not been run in years. Is there a way to test the switch for the headlight. I'm not sure which wire should have voltage in the various switch positions.


There are only two positions for the Mk3 headlamp selector switch, HEAD and PILOT.

With the sliding switch set at the HEAD position, there should be continuity between the blue [U] and the blue/yellow [UY] wires of the switch cluster.

At PILOT, the switch should be 'open'.

If checking by voltage, the blue should show volts with the switch at HEAD, and 0.V at PILOT.

Re: Testing Norton Commando MKIII headlight switches [Re: L.A.B.] #662771
08/03/16 4:03 pm
08/03/16 4:03 pm
Joined: Nov 2015
Posts: 29
Penna
D
Dnaj11 Offline OP
BritBike Forum member
Dnaj11  Offline OP
BritBike Forum member
D
Joined: Nov 2015
Posts: 29
Penna
Thank you. My ohm readings between the blue and blue and yellow correspond, but I have no lights whatsoever, and no tail light either. Is there something else common to both? Does the run/kill switch have any bearing? I do not have an owners manual for this bike. Thanks

Last edited by Dnaj11; 08/03/16 4:07 pm.
Re: Testing Norton Commando MKIII headlight switches [Re: Dnaj11] #662774
08/03/16 4:20 pm
08/03/16 4:20 pm
Joined: Mar 2006
Posts: 3,553
Norfolk, UK
L.A.B. Online content
BritBike Forum member
L.A.B.  Online Content
BritBike Forum member
Joined: Mar 2006
Posts: 3,553
Norfolk, UK
Originally Posted By Dnaj11
My ohm readings between the blue and blue and yellow correspond, but I have no lights whatsoever, and no tail light either. Is there something else common to both?


The feed to headlamp switch (blue/yellow) comes from the master/ignition switch terminal 4.

All other lights (pilot, tail, instruments) are fed from master switch terminal 3 (brown/green) so I suggest you check the wiring back to the master switch and also check you have power reaching the switch from the battery (brown/blue, terminal 1).




Originally Posted By Dnaj11
Does the run/kill switch have any bearing?


No.


Originally Posted By Dnaj11
I do not have an owners manual for this bike.


Mk3 manual:
http://britmoto.com/manuals/Manuals/850_man.pdf
Wiring diagram, Section J.

Last edited by L.A.B.; 08/03/16 4:41 pm.
Re: Testing Norton Commando MKIII headlight switches [Re: L.A.B.] #662803
08/03/16 7:40 pm
08/03/16 7:40 pm
Joined: Nov 2015
Posts: 29
Penna
D
Dnaj11 Offline OP
BritBike Forum member
Dnaj11  Offline OP
BritBike Forum member
D
Joined: Nov 2015
Posts: 29
Penna
Thank you. Looks like the switch is flakey. Other than that, I think its ready to start!




Moderated by  Dave Comeau 


Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.6.1.1
(Release build 20180111)
Page Time: 0.062s Queries: 15 (0.005s) Memory: 1.0149 MB (Peak: 1.1566 MB) Zlib disabled. Server Time: 2018-04-20 20:07:02 UTC