electrical issue

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fourperf

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Hi all, I restored a few mk 3's years back (I used to frequent this great fourm). I moved and my bikes didn't get any use in about 4 yrs (it ran great before). I put in a new battery and nothing. no electrical at all anywhere. I checked the brown/blue wire and it has power all along the harness to the switch. I tried connecting the br/bl wire to the white wire at the switch (per another thread I saw) and nothing. I have looked and looked and looked and can fine nothing other than a broken terminal on the capacitor which has nothing to do with it I think (correct?). any suggestion as to where to look next would be greatly appreciated. It has a boyer ignition (just to give the complete picture) thanks in advance
mark
 
fourperf said:
I restored a few mk 3's years back
Click to expand...

Just to confirm it is an 850 Mk3?

fourperf said:
I have looked and looked and looked and can fine nothing other than a broken terminal on the capacitor which has nothing to do with it I think (correct?).
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Not necessarily. Is it the capacitor double terminal for the two brown/blues that is broken? If so then are the two brown/blue wires still connected? If not then connect them together.
 
Hi, thanks for the reply. It is the red wire that the terminal broke off. its So frustrating. It’s also a new harness
 
fourperf said:
Hi, thanks for the reply. It is the red wire that the terminal broke off. its So frustrating. It’s also a new harness
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Ok, that's not as important so what about the harness etc. ground connections?
 
All the connections seem good. I have unplugged everything and replugged in case of corrosion. It is a new harness. when I test continuity from the positive terminal on the battery it beeps anywhere I touch on the bike (that isn’t isolated)
 
fourperf said:
All the connections seem good. I have unplugged everything and replugged in case of corrosion. It is a new harness. when I test continuity from the positive terminal on the battery it beeps anywhere I touch on the bike (that isn’t isolated)
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New main and headlamp harness sections?
The glass fuse holder connections can be dodgy.
There should at least be a harness ground (red) connection to the head steady and the heavy gauge positive starter cable connected from the crankcase to the battery positive terminal.
For brown/blue 'NU' to be connected to white 'W' at the master switch and nothing at all working would indicate a fault in the ground wiring that on the Mk3 should return to battery positive via the head steady, engine casings and finally, the heavy gauge positive starter cable and not directly to battery positive from the harness if there's a working starter motor.
 
Thanks so much. the headlamp and main harness are both new. The fuse and fuse holder both seem fine. The fuse shows continuity when tested. The Heavy gauge positive cable is connected to the crankcase from the positive terminal on the battery. I will check the headsteady ground next.
 
When you say no power, does this mean no lights anywhere or just no power to the starter system?
Try bypassing ign switch to see it that is your issue.
 
I'm also off the road with electrical probs. on the MK3.
Starter and ign. both work in position 3 and she runs , but no lights in pos. 4 .
L.A.B. I rebuilt the switch , but food (and red vino..) fell on the notes for where the wires go back on the 4 Pos. switch.
 
Torontonian said:
Starter and ign. both work in position 3 and she runs , but no lights in pos. 4 .
L.A.B. I rebuilt the switch , but food (and red vino..) fell on the notes for where the wires go back on the 4 Pos. switch.
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electrical issue
 
If there's battery power to the switch terminal and no power beyond that with the switch "on," it's the switch. Check for power at the switch output terminal (not the wire connected to it - the metal terminal itself) with the switch 'on." If there is power at the terminal but none beyond, it is a wiring connection fault/error or a broken wire.
 
MexicoMike said:
If there's battery power to the switch terminal and no power beyond that with the switch "on," it's the switch. Check for power at the switch output terminal (not the wire connected to it - the metal terminal itself) with the switch 'on." If there is power at the terminal but none beyond, it is a wiring connection fault/error or a broken wire.
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As fourperf said, brown/blue has already been connected directly to white with no change.
fourperf said:
I tried connecting the br/bl wire to the white wire at the switch (per another thread I saw) and nothing.
Click to expand...
 
fourperf said:
No lights anywhere, no horn. Completely dead
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Did you try connecting the ignition switch brown/blue NU (from battery negative) to NG (lights except for the headlamp, Edit direction indicators/blinkers brake light and console warning) and UY (headlamp only and console main beam warning lamp)?
 
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All that is different from when it worked is a new battery? Is the battery grounded to the positive terminal?
 
Torontonian said:
I'm also off the road with electrical probs. on the MK3.
Starter and ign. both work in position 3 and she runs , but no lights in pos. 4 .
L.A.B. I rebuilt the switch , but food (and red vino..) fell on the notes for where the wires go back on the 4 Pos. switch.
Click to expand...
I'm getting a power up reset on both E- instruments with the key in position 2.
 
Torontonian said:
I'm getting a power up reset on both E- instruments with the key in position 2.
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By "position 2" do you mean 'OFF' or the 'Parking lights' key position?
I assume that's not what's supposed to happen with electronic instruments so is a new problem since rebuilding the switch?
Does it have the Canadian model ignition switch and automatic lights on with ignition unit/assimilator although I'm not sure if that is significant when using electronic instruments or not?
 
L.A.B. said:
As fourperf said, brown/blue has already been connected directly to white with no change.
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If I'm understanding what has been described, That is not possible.

If the Brown/Blue wire has power and the white wire is connected to it, unless the connection between the two is bad, then the white wire now has power...at least to the point where the wire is broken or corroded internally, the next connection is bad, etc. The electricity cannot just disappear unless the fuse blows.

Connect the brown/blue and white wires. Check the circuit at the next point where the white wire connects to anything. If there is no power, check the white wire's continuity between it's connection at the blue/brown and that next connection point.
 
MexicoMike said:
Edit: If I'm understanding what has been described, That is not possible.
Click to expand...
MexicoMike said:
If the Brown/Blue wire has power and the white wire is connected to it, unless the connection between the two is bad, then the white wire now has power...at least to the point where the wire is broken or corroded internally,
Click to expand...

Therefore, is possible as what fourperf actually said was... "I tried connecting the br/bl wire to the white wire at the switch (per another thread I saw) and nothing."

...he didn't say no voltage at W, only that connecting NU to W at the ignition switch resulted in "nothing" working as I understand it.

Also for it to work relies on the W circuits having a 'ground'.

Edit: For ignition and lights then all four ignition switch wires (NU, W, NG and UY) must be connected.
 
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