1990 1500SE electrics

[John Glover]

I have this problem, when the bike is on centre stand and in neutral all systems lights etc work as they should.
When any gear is selected and you switch left or right indicator the back lights all flash dimly, and no hazards work when selected.
Where do I look to sort it out? All relays and fuses are good reverse diode is also good. Why only when a gear is selected ?

[offcenter]

Hmm....That's a bad ground somewhere.
Hopefully someone here can tell you where to look.

[MikeB]

I would suspect it is a ground issue.

Under the seat on the left and right hand sides near the frame tubes near the top of the shocks are two multi conductor plugs stowed away inside a plastic clam shell type of box.

The connector on the left hand side is where I suspect your issue is. Open the box and separate the connectors and take a close look at the condition of the wires and connections. I suspect you will see the offending connections immediately.

Here are a few pictures for you:

[Zman457]

Great, now I need to pull the seat on mine and check that out now. I'm not having any issues, but it's worth a look.
Is that a ground wire? Is there any way to keep that from happening?

[MikeB]

Yup, it's a ground connection.

Keeping the connections clean and tight is the way to prevent it but there are lots of connectors on these machines. It's really difficult to insure all the connections on the bike are 100%.

[Charlie1Horse]

If the connector pins are clean, pack the connector with die-lectric grease to keep moisture from causing the pins to corrode. Then you shouldn't have a problem with it. The die-lectric grease doesn't actually promote connectivity but it keeps moisture from causing corrosion, poor connections, and heat which CAN cause a fire.
Russell