neutral light always on

[fermin]

After changing the neutral switch and grinning upon finding the green neutral light on, I was dissapointed when it didnt turn off after engaging gears.  I thought I read somewhere about this being caused by a bad diode board, but havent been able to find the article.  Any other suggestions?

[Bob_Roller]

The diode that causes the neutral light to come on, is in the starter relay circuit, and it only comes on when the clutch lever is pulled in if this diode is bad .

[fermin]

Thanks Bob, its always on, with or without the clutch. Same switch as the one it replaced. ANy other suggestions?

[Bob_Roller]

Somewhere in the neutral light circuit, you have an unauthorized path to ground .

Around the left side cover, there is an electrical connector should be a two wire connector,  usually ty-wrapped to the frame .

One wire is for the neutral switch, the other is for the low oil pressure switch .

Disconnect that connector and see what happens, you should have lost both the neutral light and the low oil pressure light with the key in the 'ON' position .

[fermin]

Yes, both indicator lights go out when the connector is open.  What next follow the live wire ?

[Bob_Roller]

You can try another test to check the wiring from this connector, back to the neutral light in the tachometer .

Take a piece of bare wire, touch it to one of the pins on the neutral light side of the connector to the transmission case, with the key in the 'ON' position either the low oil pressure light or the neutral light will come, try both, until the neutral light comes on .

If this works, I'd have to say you have a wire problem between the connector and the neutral switch .

 I went back and read your previous posts, you stated that you replaced the switch with the same one that was removed .

Do you have the BMW part number available for the switch you just installed, there are two different neutral switches, they work opposite of each other .

The number you should have is : 61311243097 .

If you have the correct switch, there most likely is a problem with the wiring from the connector you just removed, to the switch itself .

[fermin]

Yep thats the part number ordered and installed , what do you mean the 'neutral light side of the connector'?  wire to one of the two switch connectors to ground?

[Bob_Roller]

The side of the connector that goes to the light, that should be the upper side of the connector when it's disconnected .

Touch the bare wire to one of the metal contacts in that side of the connector the other end of the wire, place it on the transmission case .

[fermin]

Bob,

both the neutral  and the oil lights come on upon separating the connector and touching the individual upper connector and the transmission case

Upon joining the connector the neutral light stays on permanently....

[Bob_Roller]

You've got a problem with the wire from the connector to the neutral switch .

[fermin]

OK, well thats a short cable I'll try  new wire see what happens.

Danke

[Bob_Roller]

With the ignition switch on, there is power to the switch, it needs the switch to close and then go through the brown wire to the ground connection at the transmission bolt on the left side of the bike .

Can you see any missing insulation on the wire from the connector to the switch, if you have bare wire if it touches any other bare metal like the transmission case or engine case, it will complete the circuit and turn the light on, regardless what position the switch is in .