Very strange problem: horn+indicators

Have you cleaned the frame earth?
It is located on the right hand side near the rear brake MC

 

I haven't touched it yet. But yes, good point, I will do it next weekend. Thank you.

 

Checked all earths, cleaned every connector etc. I am buying cheap horn to test it out next week and will revert back to you.

 

Swapped for a new horn. Indicators on dashboard just flashed slightly when pressing horn, and then stay off while horn ON. I connected old one pressed horn kept pressing and indicators come on and stay ON till horn released. Old horn in louder than new so probably different load... I checked ALL earths , cleaned etc. No improvement. Now I will be looking at clocks back panel..

 

Hmmm, it is strange.
I can't remember if the 5G has one or two cables going to horn, mine was modified long ago.
If it's happening with horn, it must be because the horn earth is no good.
You need to look at where that earth is, also look at the relay for the horn and where that gets its earth from.
I would still suspect the earth block, even though you've cleaned it.
It is why so many people have got rid of it, including me.
Another thing you could try is earthing the horn directly to battery and try again.
Then earthing the relay direct and trying it.
My suggestion is that getting rid of the earth block takes away a known problem spot, no matter how clean it looks.
Then you can be sure problem is elsewhere.

 

2 cables going into horn. I cleaned all connectors on the horn and connectors going into the horn. I also opened the switch cleaned everything there. In regards to relay, both horn cables run from the horn to the switch, that's all. Will have to track it somehow.. I actually cut off the earth block, soldered it and problem still occurs . I will try the battery trick next weekend and will try to track down that relay too. I appreciate your help!

 

One more thing: I have LED lights installed in the dashboard. I will change indicators to old bulbs and see what's the story.

 

The black/ brown is power feed for the horn, it also provides power to the indicator relay and both brake light switches.

Does anything happen when you use the front brake?

What happens when you earth the horn directly to the frame or engine?

I'm thinking dicky earth or duff relay.

 

Hi. Nothing happens when I use front brake. Did not try earthing horn straight to battery and I will try it next weekend and get back to you for sure. Do you know where is the horn relay?

 

Not the horn relay it’s the indicator relay.

Also try removing th3 relay

 

Hi. Update:

1. I connected the earth from the horn directly to the battery. Result: the same problem, indicators on dashboard light up.
2. I left horn's earth connected to the battery and removed tail light, removed left indicator bulb(not dashboard) in the front. Result: when the left indicator bulb was removed and I pressed horn, then left dashboard indicator light came up but very little. The right dashboard indicator came up stronger as the right indicator bulb was in.
3. I removed from dashboard my LED indicator bulbs and installed old original ones. Pressed horn. Result: none of them lighted up, not even slightly (total darkness in the shed). I believe old bulbs need more power to light up.
4. I removed from dashboard both indicator bulbs and I measured voltage where bulbs connect behind the panels on ignition on, but engine off. Result: 0.04V
5. I pressed horn while volt meter was connected to the places where dashboard indicator bulbs connect. Result: 5.4V.
6. Disconnected relay completely, pressed horn. Result: dashboard indicators light up. Strange.

I am now suspecting faulty relay, but it will be next week till I get it. If you guys have other ideas I would be happy to hear them.

Thanks fck that my new fairing are getting sprayed and I can work on the bike...

 

Update: Got new relay today. The same thing happens.

 

See if this helps:

 

Yes, have this diagram in my Honda manual. I tried to track everything. Madness. Maybe it is made this way. Someone in motorbike shop told me that when I change to LEDs I must add inline resistors etc. I think he might be right.

 

Did you disconnect the correct relay?

The problem when you install led instead of filaments is that you need to add resistance in order to balance out the load. Especially in indicators in order that they flash at the correct rate. Are the led installed the correct way?

 

I don't believe that LEDs, inline resistors or relays are a problem here. The shared parts of the horn and indicator lights circuit is the common earth and also the black 9p connector that joins the bar switches to the main harness. Can't do any harm to disconnect the 9p connector and give it a good squirt with contact cleaner and follow up with dielectric grease. I'd also check that the cables in that area are free of chafing.

 

Yes, I wrote I completely removed relay. LED lights are only installed in dashboard, flashers outside are normal bulbs. They flash at normal rate too. LEDs are installed correct way.

 

Today I changed all relays for new ones. Horn earth was run from horn directly to the battery. The same thing. Spent 7 hours today and took wiring apart, bit by bit, cleaned even thing that were clean and healthy. Then a friend came up with his VFR , the same year, we changed bulbs for LED ( new ones and then mine) the same thing. When he presses his horn he gets about 5V at the back of the panel where indicator bulb goes in. The same.