Main loom.

[ME 109]

I had a look on my loom for an earth Steve, but the loom disappears into the great unknown.
I would assume there is an earth in that loom, where it terminates on the bike I don't know.
George has a good point with the contacts in the plug.
It may also be one power wire causing the problem. It may power several lights?
George, re the contacts in the plug, is it likely to cause the failure of several lights?
Perhaps as I wrote above if one power wire is causing the problem then a contact is still a candidate.

[Airbear]

G'day Steve. Intermittents are a bastard, and that fekkin' plug to the instruments is an even bigger bastard.

I'd be doing what George Ryals suggests first, then if it still appears to be the wires ...

Looking at the diagram in Haynes it appears that the green/blue wire to pin 8 supplies power to the Gen, Neutral and Oil lights, and that is the likely culprit. The brown wire to pin 12 is only earthing the back lights to the speedo and tach, plus the High Beam light, so is not an issue in this case. The black wire from the coil to pin 10 is almost certainly supplying a pulse to the electronic tach.

If you are prepared to hack a plug off one of your other looms and graft it on, I suggest you start by using a screw terminal block - one of these ...



Just match the wires leaving a good length of slack, plug it in and go for a quick ride to check that everything works. Then you can confidently (or otherwise) solder and heatshrink wire by wire. An alternative is to use straight crimp connectors, the red ones are the right size. Super Cheap Auto has very good ratchet crimping pliers for about $17.

ps: Another possibility is that the green/blue wire is dodgy further down. The starter relay is under the tank, and it might be worth pulling the tank off to check that all is well there before you do anything else. Manipulating the wire could be affecting a connection back there. Just a thought. Good luck.

[dwerbil]

A few years ago, I had quick failure of idiot lights in the /7 instrument lights. I opened the cluster, and upon inspection found the circuit board starting to delaminate. Another 60 bucks for a new one plus new bulbs, the cluster has worked flawlessly since then.

[SteveD]

Thanks for the replies. All very helpful, and confirms a little in my mind how to proceed.

In reply to the suggestions, 1 x 1.
1. The connectors in the plugs: all clean, no corrosion. The connection points all look fine.

2. Reconnecting. Charlie, that was just what I had in mind. I'm in transit to the rest of my family function. I'll get to it tonight. The area lower down I plan to open up and test the blue/green wire there, and also 2-3 inches from the terminal plug.

3. Randy, the board is pristine. The one in the spare isn't unfortunately.

[SteveD]

The blue mark is where I think the culprit is. The blue piece is much longer than the diagram presents.

[grant81rs]

The black wire from the coil to pin 10 is almost certainly supplying a pulse to the electronic tach.

Sorry to cut in here on the topic but could this wire/connection cause my tacho to show faulty...It is showing 500rpms slower when operating, acting a little sluggish alround and again everything in the tacho housing is clean as I have had it all undo many times to sort this out....

Goodluck steveD with the bike and talk to you thru the week....

[SteveD]

Things are deteriorating rapidly unfortunately.

I went back to it, and confirmed that the connection at the back of the instrument is where the problem is. Whether it's the plug, or the pins on the circuit board is uncertain. Certainly either wriggling the group of wires and/or compressing the plug allowed the lights to stay on.

However...don't you hate the "however"...The bike now won't start. Clack, clack, clack is all I get. I can feel the starter relay moving inside if I touch it. The headlight and taillight were on, despite the ignition being off.

So I opened the headlight and checked the fuses...they're both fine and clean. I also checked the earth connections on the circuit board the fuses sit on. They appeared fine.

I tried again at the starter, which clacked again and gave a short "quiet" squeal, and I could smell smoke. I saw sparks at the batteries negative terminal, which wasn't firmly attached. The connection there got hot and it is now marked. I'm hoping that tightening the negative at the battery (not the g/box) will sort this.

I couldn't smell smoke anywhere, or see any damage except at the neg terminal. The battery reads 12.48 ignition off, at the terminals.

Before I touch it again, any advice? Please.

[SteveD]

The black wire from the coil to pin 10 is almost certainly supplying a pulse to the electronic tach.

Sorry to cut in here on the topic but could this wire/connection cause my tacho to show faulty...It is showing 500rpms slower when operating, acting a little sluggish alround and again everything in the tacho housing is clean as I have had it all undo many times to sort this out....

Goodluck steveD with the bike and talk to you thru the week....

Are the connections clean? I think the black goes to terminal one on the right side coil.

[SteveD]

Charlie called and we had a reassuring chat. I've reconnected the battery nice and tight, but it still clacks. Bugger. The battery now reads 12.14 at the terminals. I might put it on charge overnight.

As we spoke I was reminded of how I cleaned the circuit board pins...a light clean up with a small dremel type tool. We wonder if George had it right. The cleaning might have loosened the connection.

You can sometimes use a dental pick to reach into the holes in the plug and spring the comtact pieces toward the center of the hole. Hopefully reestablish contact.

edit: I've just used my spare instruments as a tester...the neutral light comes on and off just like the other one. The other lights don't work at all, but that circuit board is rubbish. Also substituted another starter relay. Same clacking unfortunately.

[ME 109]

double post