Help me electrical guru's, neutral light won't go off

[regder]

Been like this for a week now. Stays on solid regardless what gear I'm in, starts to fade after riding for half an hour, but returns strong after the bike has been sitting.

Neutral switch seems to work normally as it cycles on/off in the Diag menu, and the bike won't start in gear, as it should.

Any ideas? I'm guessing a short between the ecu and the gauge cluster?

 

[FinalImpact]

Ya, lift the tank disconnect the battery, then reach back and unplug the ECM. Inspect the connection for corrosion or any sort of damage. Assuming you inspected the connections at the switch (by swing arm IIRC). Again, remove and inspect for corrosion.

ECM is the large multi-conductor block.

 

[NorcoT]

Been like this for a week now. Stays on solid regardless what gear I'm in, starts to fade after riding for half an hour, but returns strong after the bike has been sitting.

Neutral switch seems to work normally as it cycles on/off in the Diag menu, and the bike won't start in gear, as it should.

Any ideas? I'm guessing a short between the ecu and the gauge cluster?

I had this before also, have you been riding in heavy rain or washed it recently? When mine did it I checked everything, and couldn't find a problem. Then I read somewhere else that other people had the same problem usually after a ride in heavy rain. So I let it dry out over a couple of days and next dry ride it was fine.. Hasn't happened since so I'm still not sure what it was

 

[regder]

Been too busy to update this.

Light was on solid for about a week. Then dimmed to almost being off for about three to four days, now is completely off. Funny thing, when it was dimmed, it would get brighter when I braked, and dimmer when I accelerated.

I do suspect water had something to do with it as it came on two days after I washed it. Hasn't really seen water since so I don't know if it will happen again.

At this point it's off so I'm not going to look into it further, if it does come back on I might though

 

[dpaul007]

It still might be in the best of your interest to track down the plug/connection that's giving you an issue. If water can get in there, it'll more than likely corrode, if it hasn't already. Clean it up and put some dielectric grease on it and plug it back in.

 

[regder]

It still might be in the best of your interest to track down the plug/connection that's giving you an issue. If water can get in there, it'll more than likely corrode, if it hasn't already. Clean it up and put some dielectric grease on it and plug it back in.

You are right, that's the plan for next time I have to take the front end apart. Take every electrical connector I see, clean it and grease it.

 

[TownsendsFJR1300]

Part #7 is the neutral switch located at the rear of the engine:

Yamaha Motorcycle Parts 2007 FZ6 - FZS6W ELECTRICAL 1 Diagram

I'd check there first, then the connector at the next connector in the harness. As posted above, dilectric grease should solve the problem once dried out...

 

[regder]

Part #7 is the neutral switch located at the rear of the engine:

I'd check there first, then the connector at the next connector in the harness. As posted above, dilectric grease should solve the problem once dried out...

That was my suspicion as well until I checked the Diag function which shows the status (on or off) of the neutral switch, The Diag screen showed the neutral switch working exactly as it should. This was confirmed by trying to start it in gear, the bike correctly didn't start, even with the light on. The bike knows if it's in neutral or not, even if the gauge indicator does not.

Haven't had time to try and figure out the electrical diagram, but I suspect somewhere between the gauge cluster and the pcm, or whatever it is that sends the signal to the indicator, there is a short of some kind.

 

[Motogiro]

That was my suspicion as well until I checked the Diag function which shows the status (on or off) of the neutral switch, The Diag screen showed the neutral switch working exactly as it should. This was confirmed by trying to start it in gear, the bike correctly didn't start, even with the light on. The bike knows if it's in neutral or not, even if the gauge indicator does not.

Haven't had time to try and figure out the electrical diagram, but I suspect somewhere between the gauge cluster and the pcm, or whatever it is that sends the signal to the indicator, there is a short of some kind.

I've looked at the schematic and the signal for the neutral light and it gets it's ground path through the starter cutout relay assembly. This unit actually is a logic control unit that has 2 relays and 10 diodes. It should not be confused with the starter relay on top of the battery. There are 2 relays in this unit. 1 for the starter interrupt and the other for fuel pump and fuel injector interrupt. Example logic: Bike is in gear, engine running and the side stand is put down = fuel pump and fuel injectors are stopped. Transmission not in neutral, clutch is not pulled = no starter relay coil completion. Cool little box!

Since the ECU sees proper logic and interrupts the starting when not in neutral I would suspect that the light green wire leaving the instrument cluster has found a path to negative ground allowing enough forward bias to light the neutral LED indicator. The B+ from key on, goes to the cluster (red with a white tracer wire),into the cluster, through a diode then through the neutral LED light. Then leaves the cluster through the light green wire where it goes into the starter cutout assembly, through another diode then leaves the starter cutout ass'y through a light blue wire and to the neutral safety switch and to ground.
This is the path that should allow the light to come on and off. Obviously the light is finding a path before the starter cutout or within the starter cutout ass'y.

I believe this unit is under the left pod. It will have a plug with 16 wires. Unplug the unit and release the pin in the plug that has the light green wire attached. Plug the unit back in without the light green wire. Is the neutral light out? If yes the Starter cutout assembly is providing a path internally. If the light is still on then the wire is chafed or getting a path to ground through another route.
Hope this helps!

 

[FinalImpact]

I've looked at the schematic and the signal for the neutral light and it gets it's ground path through the starter cutout relay assembly. This unit actually is a logic control unit that has 2 relays and 10 diodes. It should not be confused with the starter relay on top of the battery. There are 2 relays in this unit. 1 for the starter interrupt and the other for fuel pump and fuel injector interrupt. Example logic: Bike is in gear, engine running and the side stand is put down = fuel pump and fuel injectors are stopped. Transmission not in neutral, clutch is not pulled = no starter relay coil completion. Cool little box!

Since the ECU sees proper logic and interrupts the starting when not in neutral I would suspect that the light green wire leaving the instrument cluster has found a path to negative ground allowing enough forward bias to light the neutral LED indicator. The B+ from key on, goes to the cluster (red with a white tracer wire),into the cluster, through a diode then through the neutral LED light. Then leaves the cluster through the light green wire where it goes into the starter cutout assembly, through another diode then leaves the starter cutout ass'y through a light blue wire and to the neutral safety switch and to ground.
This is the path that should allow the light to come on and off. Obviously the light is finding a path before the starter cutout or within the starter cutout ass'y.

I believe this unit is under the left pod. It will have a plug with 16 wires. Unplug the unit and release the pin in the plug that has the light green wire attached. Plug the unit back in without the light green wire. Is the neutral light out? If yes the Starter cutout assembly is providing a path internally. If the light is still on then the wire is chafed or getting a path to ground through another route.
Hope this helps!

I see a REP point in your future for that one.. .. .. :thumbup: :rockon: :thumbup:

 

[FinalImpact]

I see a REP point in your future for that one.. .. .. :thumbup: :rockon: :thumbup:

Crappers - DENIED! "You must spread some Reputation around before giving it to Motogiro again."

I'll keep you in mind! :BLAA:

 

[regder]

That is some awesome info Motogiro, thanks!

 

[TownsendsFJR1300]

Yepper, Cliff's the electrical Giro!! When in doubt, PM Cliff!! :thumbup:

 

[FinalImpact]

That is some awesome info Motogiro, thanks!

I concur! :bow::bow:

 

[Motogiro]

As others have noted: I'm wondering if where the wire attaches to the switch there is enough path on the outside of the switch to light the LED but not enough to trick the ECU. If you haven't, get to the switch, unplug it and clean all around the switch to break any path that might exist on the outside of the switch.

Something I've seen repeated over and over again. After a rain or washing/power washing, the bike run crappy or indicators or instrument reading are off.

One of the big contaminates is salt. You might live on the coast near the ocean where weather or waves get salt on roads as well as area with snow and ice removal. Salt is often added to sand in areas that get icing. Want to see an example? Put 2 electrodes in a glass of water and put the meter on a range to measure resistance. Now add a little salt. You will see the current going through the water rapidly increase. Or watch how fast vehicles that live on salted roads rust away!
Many of the signals the ECU sends and receives can be largely effected by salt contamination at plugs etc.
My recommendation is to open a suspected plug and rinse with water. The reason I suggest water is the salt is instantly soluble with water as opposed to petroleum products. The water will get rid of the salt quickly where oil product will not. You want the salt gone as fast as possible because it will also damage the contacts in connectors. Then blow the plugs/connectors dry with compressed air. After this you can use a petrol product to treat and lessen future contamination.

 

[TownsendsFJR1300]

Any updates?

 

[regder]

Any updates?

The light went off on it's own a while ago so I can't diagnose it until it comes back on. Haven't washed it since before it came on though. Just got back from Chicago and the bike is filthy as hell so I'll have to wash it sooner than later. Will see if the light comes on after that.