Electrical fault

[scooter paul]

1981 R80 G/S. No headlight dip or main. No front indicators. Everything else fine! Checked the two fuses under the tank. Before I get into the headlamp bowl to see if anything has come adrift has anyone got an idea please.
Thanks, Paul.

 

[Edward]

Paul, replace the fuse or try swapping the two over. They can look fine and even test fine but have a minute, almost invisible fracture. I spent two days tracing a fault on my RT and it was the fuse. The fracture closed when I handled the fuse to test it with a meter. Of course it may not be that but worth trying. As always please be aware I know sweet FA.

 

[Rob Farmer]

Since the front and rear indicators are physically wired together I'd say the problem is the electrical ground for the front indicators and headlight. Do the idiot lights flash and work as they should and do the rear indicators flash at twice their normal rate?

According to the wiring diagram they should be wired independently to ground at point 31. I'd start by measuring continuity to ground from the indicators and headlight.

 

[solidstate100]

I think Rob might be on to something. If I remember correctly (not a given!) point 31 is within the headlamp shell, so its possible that the earth wire may have fractured in the loom where it passes out of the headlamp shell and between the front mudguard and on to the headstock then to the earth point - That bit of loom is a known failure point and its recommended to space the front guard a bit lower to reduce pinching to the loom in that area.

 

[scooter paul]

Thanks. That sound like a good punt. It is just the headlight and the front indicators as I originally posted. No idiot light for indicators and the rears flash at double the rate. Tomorrows job! I'll report back.
Paul

 

[Rob Farmer]

So we need to redefine the comment about "every thing else works"

In that case there's a possibility the connector block coming off the dip switch has come adrift. If this has come adrift the rear indicators will still work, the front will not and the indicator idiot warning lights would not work.

My moneys on the connector block having been pulled apart

 

[solidstate100]

Ahhh, now we have the full symptoms............Rob may well be right.

I had a recent intermittent indicator fault (different symptoms to yours) and it turns out that the connector block Rob mentions (under the tank) was loose/dirty/greasy.Cleaned it all up, jobs a good un. Thats where I would start, work back from there.

 

[scooter paul]

Thanks chaps. A perfect diagnosis. 10 minute fix. Just enough tension on left lock to pull it out. Why it's decided to do it now I've no idea. A cable tie is now ensuring it won't happen again. One of the many reasons I love Airheads and still use it for touring is how easy the are to fix. My RnineT would have been a lot more complicated.
Paul.