R100gs - indicator problem????

[barny]

Currently got me stumped, engine running LH indicator flashes once and stops front and rear the same. RH operates fine front and rear. Switch off the engine switch on the ignition, indicators LH and RH front and back all working correctly. I am looking at the wiring diagram and cannot see reason for the difference engine on or off. Initially thought it was the indicator relay and control unit but its not that old. Also if I hold the LH button (engine running) the indicator will flash. Its got to be a connected to the engine running but on the LH indicator only. ???
Help
Barny

 

[Posh Pete]

Engine vibes causing an earth issue? Check inside the LH indicator pods?

 

[Gelandestrasse]

Have a go undoing the flasher relay connector and reconnecting - could be corrosion in connector. Also both switch connectors. Just to ensure corrosion hasn't built up on connections.

 

[mikeyboy]

What year bike,
Early bikes have 3 pin flasher relay and normal toggle switch on LH side
Later ones have paddle switches and a control unit

 

[barny]

Mikey, it's 1995- 3 separate switch handle bar units with the large control unit under the tank.

 

[Stirlingmoz]

Mikey, it's 1995- 3 separate switch handle bar units with the large control unit under the tank.

I might have a control unit if yours proves to be faulty.

Can take a picture if you wish ?

 

[Stirlingmoz]

This is the unit I have..

 

[barny]

That's the same as mine. I'll keep that in mind. Could you DM me the price please.

 

[mikeyboy]

Worth spending a bit of time with a wiring diagram checking obvious connectors for corrosion,
But if you can get your mitts on a known good control unit to swap it would save some time and head scratching,
I may have one but won’t have time to look till next week as I’m away
Also worth doing some basic voltage tests on the charging circuit,
If it’s over charging it may be freaking the indicator control unit

 

[graham_cj]

This may seem a strange answer but I suspect your HT leads are faulty
The flasher unit is electronic and is picking up interference from the HT leads
I had the same problem with my GS. When the engine not running indicators working ok
Engine running above 4000 rpm working ok
Engine running below 4000 rpm right indicator ok left 1 flash only but if I held left indicator button it would flash as normal (same problem as you are having)
I have a second bike so started swapping out components
Tried flasher, unit bean can , ignition trigger unit, diode board and coil
Problem was still there, all components working ok on second bike
After some thought swapped HT leads GS indicators working ok
Donor bike indicators now faulty
I found one of the HT caused the problem, new set fitted and no problem. Since

 

[barny]

You may have shone a light on something. I have recently changed my plug caps to non resister ones, prior to that I had an MOT so all was OK then, changed caps now have a problem. I will confirm later and thanks for giving me something that I have effected recently.

Barny

 

[barny]

Graham, I cannot thank you enough. I have just changed the plug caps back to the ones previously fitted. Ran the engine and INDICATORS ARE WORKING normally. I would never have connected the two things now need to find the if the 5 OHM plug caps are correct.

 

[graham_cj]

I'm glad you got it sorted
When I tried to find fault, I spent many hours swapping bits over. I changed the complete charging and ignition system only to find it was a 2 minute job to replace HT lead

 

[DrFarkoff]

if the 5 OHM plug caps are correct.

5 Kilo Ohm