Is there a nice clear diagram of the underside of the Mark III ignition switch?

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nortonmargie

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I rewired the headlight shell and the blinkers work, the bike starts,and the neutral light goes on, BUT the headlight doesn't work and neither does the alternator light. I think I might have put the spade connectors on the wrong prongs.
 
Is there a nice clear diagram of the underside of the Mark III ignition switch?
 
nortonmargie said:
THANK YOU!
Click to expand...
:)

If it wasn't the connectors on the wrong terminals then there can be various reasons why the red ignition/charge warning lamp doesn't work especially if it has the old 3AW, 3-terminal silver can assimilator although presumably, the light was working before the rewire?

The console harness section colours do not match the Mk3 wiring diagram but match the main harness.
Also, the two W wires from ignition switch terminal 2 do not appear to be included in either the switch or console replacement harness sections (if they ever were)!
Is there a nice clear diagram of the underside of the Mark III ignition switch?


As for the headlamp, UY from the master/ignition switch terminal 4 normally runs to the R/H "HEAD - PILOT" switch and then out, as blue (U) going to the L/H switch cluster where it connects to UY (at the multi-pin plug).
 
nortonmargie said:
I rewired the headlight shell and the blinkers work, the bike starts,and the neutral light goes on, BUT the headlight doesn't work and neither does the alternator light. I think I might have put the spade connectors on the wrong prongs.
Click to expand...
Made the same boo-boo a couple weeks back. Wasn't the switch at all just an internally slow shorting Chinese battery . Did not make notes on the connectors and L.A.B. sent us the photo thank god.
 
thank you for additional information. My mission for tomorrow is to figure this out. Both the red light AND the headlight were working before I replaced the (old and ratty) harness
 
nortonmargie said:
thank you for additional information. My mission for tomorrow is to figure this out. Both the red light AND the headlight were working before I replaced the (old and ratty) harness
Click to expand...
You could open up the switch itself and clean it up , not that difficult.
 
nortonmargie said:
Both the red light AND the headlight were working before I replaced the (old and ratty) harness
Click to expand...

If you don't manage to work it out then was it only the headlamp section you replaced (bought from a parts supplier, or did you make it?) or have you also replaced the main (or other) harness section?
 
I only replaced the headlight section and bought the harness from Old Britts before they (unhappily) closed shop
 
Ok, the console harness section connects to the main harness so replacing the headlamp section shouldn't have changed anything as long as the red charge warning lamp still has power (W) from ignition switch terminal 2.
 
L.A.B. said:
Ok, the console harness section connects to the main harness so replacing the headlamp section shouldn't have changed anything as long as the red charge warning lamp still has power (W) from ignition switch terminal 2.
Click to expand...
I just checked - it doesn't. Also the green light stopped working when I pulled off and replaced the spade connectors to check for dirt, bad connection etc. Aargh. One item - the Old Britts harness had the wrong connectors to the main harness (bullets instead of the plastic case items) and I cut the wires and soldered/shrinkwrapped the new harness to the old connections. Something might have gone wrong there, although I checked all wires for continuity before installing. Will check after lunch. Thank you for all of your help!!
 
nortonmargie said:
Also - should there be two or three spade connectors with white wire connected to the ignition?
Click to expand...

Ignition switch?

The headlamp harness W connector on one T2 tab and as far as I know, a spade with double(?) white W wires on the other T2, one W connects to the green neutral light and the other W to the red ignition charge warning light and seems to be a short additional W section as mentioned previously, that particular section doesn't seem to be part of the headlamp ignition switch section or console harness section as there are no spare W wires with the small warning light spade terminals anywhere and it isn't available as a separate section so needs to be made.

Perhaps some of our other Mk3-owning members could comment on where the neutral and ignition warning lights get power from?
 
Last edited:
There is a spade with double white wires. The headlight just started working, why I have no idea. I believe there is a short someplace, which I am trying to track down. Coffee, a multimeter and patience...
 
nortonmargie said:
There is a spade with double white wires. The headlight just started working, why I have no idea. I believe there is a short someplace, which I am trying to track down. Coffee, a multimeter and patience...
Click to expand...
Woo HOO! I found a loose white wire and connected it! The neutral light AND the headlight now work! Now I just have to track down the alternator light and fix the primary case leak! Progress!
 
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