Neutral light on when clutch pulled in

[grant90]

My 205 R1100s's neutral light stays on when the clutch is pulled in - with a bit of research on the net, there seems to be a view that this is caused by the clutch diode being faulty ( is that right ? )

If so , can anyone advise just where on the bike this diode resides, so I can find it and change it to fix the problem ?

 

Thanks

Grant

[dirtrider]

Evening Grant

 

I presume you mean the neutral light “comes on” every time the clutch lever is pulled in (correct?). The neutral light “should” stay on with the clutch pulled in with the trans in neutral.

 

Assuming the problem is: That the neutral light “comes on” every time the clutch lever is pulled in AND the trans is in gear then it probably is the clutch switch circuit to neutral switch circuit isolation diode shorted. Problem is, they usually go open not shorted, and an open diode won’t cause your problem.

 

In any case, most of those clutch circuit isolation diodes are in the starter relay but I have a wire diagram showing the 1100S as slightly different & not in the starter relay (at least on the pre 05 as I don’t have anything for the 05)

 

Where it’s at in that S is something I don’t know. So, maybe start by removing the starter relay as a test, if the problem goes away then your diode is probably in the starter relay. If the problem still exists then you will have to look in the wire harness in the wire between the starter relay & the neutral light (after the clutch switch wire tie in junction) (probably not too far from the fuel box).

 

[grant90]

OK to clarify - in nuetral, the light is on, if I pull the clutch in and change into 1st gear the light stays on , if I move off in first gear the light stays on ...change into 2nd and it goes out with the clutch home. Pull the clutch in again and the light comes on, 3rd gear it goes out- so effectively the light comes on while changing gear with the clutch in ..but goes out in any gear but 1st ..weird

The guy I bought it off said it had done this since he got it back from an alarm installer ..I have subsequently disconnected the alarm from the battery ( as it runs it down when the bike's not being used much) but the neutral light behaviour remains - so I suspect the alarm fitting and neutral problem were perhaps

not connected , just co-incidental

 

Thanks

 

[dirtrider]

Evening Grant

 

 

That is very strange indeed.

 

With that 1st gear thing it doesn’t point to the clutch lever switch diode & with the neutral light acting differently in the higher gears it really doesn’t act like the trans neutral switch either.

 

Maybe as another diagnostic point see if will try to crank in gear with the clutch engaged (hand off lever). Be very careful in doing that test.

 

I wonder if that alarm is somehow tied into the starter circuit effectively bypassing that diode?

 

What happens if you remove the starter relay then with the key on do a static clutch & trans shift test while watching the neutral light.

 

[grant90]

Sorry I just checked - the nuetral light stays on when the clutch is pulled in , but it goes out in any gear when released ...so are you saying that the neutral light being on when the clutch is pulled in is normal ? if it is that means there is no problem , its just weird thats all - makes it hard to find neutral if the lights on if the clutch is in..

 

Thanks

[dirtrider]

- the nuetral light stays on when the clutch is pulled in , but it goes out in any gear when released ...so are you saying that the neutral light being on when the clutch is pulled in is normal

 

Evening Grant

 

No that’s not normal.

 

In Neutral the light should be on all the time. With the trans in gear it should NEVER be on even with the clutch pulled in.

 

How does it act with the starter relay removed?

 

 

[grant90]

I have quite a lot of mechanical ability , but have never worked on this bike, so dont even know where to start looking for the starter relay - I need to find a manual - can you point me to one online anywhere ?

Thanks

[Jim Moore]

There are two one-inch square relays in your fuse box. One is the cat code plug. The other is the starter relay. Pull one out. If the bike still starts that's the CCP. If not, it's the starter relay.

 

Btw, 14 years and 240K miles on oilheads, I've never heard of that problem.

[AndyS]

I have quite a lot of mechanical ability , but have never worked on this bike, so dont even know where to start looking for the starter relay - I need to find a manual - can you point me to one online anywhere ?

Thanks

 

Here is the 1150RT fuse box, I would have thought relay location would be the same

[dirtrider]

Morning Grant

 

That 05 S you have is a bit unique & I have nothing specifically for that bike.

 

On most of the other oilhead bikes of that era the starter relay is the far left (side stand side) relay in the front row in the fuse box.

 

As far as a manual goes that might be a bit difficult. Your 05 S is kind of a unique bike. For most things the standard oilhead manual will work if you already know what you are looking for (easy to find that manual).

But if you are going to rely on the manual for every little detail & location of things then you really need to find a specific manual covering the 05 S (that won’t be easy) --I have a lot of manuals and nothing on the BMW 05 S.

 

[grant90]

The bike was first reg in 2005, but thats not to say it is an 05 model - it is probably more like an 02-04 from pictures on the web

its dakar yellow / black which came out in 03, but dont know if it was still available in later years.

[AndyS]

The bike was first reg in 2005, but thats not to say it is an 05 model - it is probably more like an 02-04 from pictures on the web

its dakar yellow / black which came out in 03, but dont know if it was still available in later years.

 

You can work out its age from its VIN plate.