Power running throught wiring without key switched on

Littlefeat69

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Am hooking up new wiring harness..ww 190882..54960723 along with headlight loom. While pondering the next move, touched the wires for warning light assimilator .. (aware of that confusing problem) against the gearbox cover and sparks . Battery is hooked up and master switch is also hooked up but key is on bench... I will also say the horn Blu once and it not ever hooked up...believe a ghost for a cross the pond is hovering..74 norton 850
 

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Ron L

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Is the brown with blue tracer (2 wires) going to terminal marked 1 on the switch? Those wires come from the battery and blue capacitor and provide power to the switch. The white with brown tracer wire to the assimilator comes from the warning light which is fed by the white wire which comes from terminal marked 2 on the switch which should be switched power. The other wires to the assimilator are ground and AC power from the alternator. Neither can have current unless the engine is turning.

Hope this helps.
 

L.A.B.

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Am hooking up new wiring harness..ww 190882..54960723 along with headlight loom. While pondering the next move, touched the wires for warning light assimilator .. (aware of that confusing problem) against the gearbox cover and sparks

The brown/blue and red wires marked "Warning light assimilator" on the Trust Lucas diagram are incorrectly marked. Those wires go to the auxiliary socket.
If you touched the brown/blue to ground then you would get sparks (and a blown fuse if more than briefly) as it would be live/hot with the ignition off.

The assimilator wires are the three marked "Blue lamp flasher unit".
Edit: Also:
The "R/H indicator" should be green/white and L/H, green/red.
The white/yellow "Ballast/Coils" wires would have been white/purple, originally.
What looks like a green/yellow at the master switch should be blue/yellow.

s-l1600.jpg
 
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Littlefeat69

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Is the brown with blue tracer (2 wires) going to terminal marked 1 on the switch? Those wires come from the battery and blue capacitor and provide power to the switch. The white with brown tracer wire to the assimilator comes from the warning light which is fed by the white wire which comes from terminal marked 2 on the switch which should be switched power. The other wires to the assimilator are ground and AC power from the alternator. Neither can have current unless the engine is turning.

Hope this helps.
 

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marshg246

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Am hooking up new wiring harness..ww 190882..54960723 along with headlight loom. While pondering the next move, touched the wires for warning light assimilator .. (aware of that confusing problem) against the gearbox cover and sparks . Battery is hooked up and master switch is also hooked up but key is on bench... I will also say the horn Blu once and it not ever hooked up...believe a ghost for a cross the pond is hovering..74 norton 850
On most of those switches, the key will come out in the off and parking position. Going clockwise looking from the side where the key is inserted. Parking, Off, Ignition Only, Ignition and Lights.
 

L.A.B.

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On most of those switches, the key will come out in the off and parking position. Going clockwise looking from the side where the key is inserted. Parking, Off, Ignition Only, Ignition and Lights.

However, if it was the brown/blue incorrectly marked as an "assimilator" wire on the Lucas diagram that touched the gearbox case (and what looks as if it might be in the picture) and not an actual assimilator wire as there should be no power to the assimilator at Parking or Off and the ignition switch wires look as if they are connected correctly then that would probably explain it.

Fitting a wiring harness with the battery connected in my opinion is inadvisable (to put it politely). :)
 

YING

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Check to see if the wire coming from the rectifier is hooked up directly to the battery.Not the switch.I just went through this with mine.Everything worked but the bike would not shut off. I had the rectifier going to the hot side of the switch.Changed it to the battery and all is well.
 

L.A.B.

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Check to see if the wire coming from the rectifier is hooked up directly to the battery.Not the switch.

I had the rectifier going to the hot side of the switch.


I can't see how that would be possible on a '71-'74 unless the rectifier wiring had been modified from standard or the brown/blue battery wire connected to the wrong ignition switch terminal as the battery and rectifier are both connected to the same brown/blue with no separate rectifier connection at the ignition switch, therefore, if the rectifier had been connected to the wrong side of the ignition switch then so should the battery.
1972-onwards-Commando-Original.png


According to the previous picture of the switch connections, they appear to be connected correctly.
Perhaps it is being overlooked that the brown/blue between the battery (-) and the ignition switch is 'hot'.
 

Littlefeat69

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Check to see if the wire coming from the rectifier is hooked up directly to the battery.Not the switch.I just went through this with mine.Everything worked but the bike would not shut off. I had the rectifier going to the hot side of the switch.Changed it to the battery and all is well.
Would that be blue/ brown and drown /blue wire and + or - on battery
 

marshg246

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Would that be blue/ brown and drown /blue wire and + or - on battery
If you connect everything as the diagram L.A.B provided, keeping in mind the corrections he gave to the Lucas harness diagram, everything will work.

What YING said is true if you hook the rectifier/Zener/Capacitor to the white wires rather than the Brown/Blue. With solid state regulators, especially PODtronics, it is tempting to do that so that there is no current draw with the key off; but then you can only kill the engine, you cannot shut it off with the ignition key.
 

L.A.B.

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Would that be blue/ brown and drown /blue wire and + or - on battery

Hopefully, you can see a large colour diagram in my previous post showing brown/blue connecting battery(-) to the ignition switch terminal 1 (double brown/blue into a single female spade terminal as your ignition switch picture shows).
Battery positive as the diagram shows is red.
As I said, I'm guessing the wire that sparked was the brown/blue which will be hot with the battery connected and the ignition switch 'OFF'.
 

YING

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LAB,
I should have been more specific.I am using a Centech fuse block and had the wire from the rectifier going to the hot side of the block trying to simplify the number of wires at the battery.At that point the bike would not shut off.
Took the wire off the block and ran it directly to battery and all is well
9D7BEDB4-8C95-4558-9925-5B1793150F69.jpeg
 
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