06 TE250 Neutral Switch. Need some electrical guru help!

[kereams]

I recently purchased a nicely used TE250 with an Athena 300 kit and all the goodies. Well maintained and documented. The only issue at all is that the neutral switch does not illuminate when in Neutral. As silly as it is, the wife really wants the light.

I have searched here and seen several threads for "Neutral Switch Issues" for the newer fuel injected bikes, but none related to the carbed bikes.

Looking at the circuit diagram (attached) in the manual one would assume that all the neutral switch does is provide a ground for the light circuit but it does not appear to work that way. Regardless of what gear or neutral I always have 12V between Pin #1 (Vbat +) and Pint #16 (Neutral Switch). I have tried opening the circuit, no success. I have tried jumping the Yellow/Green wire to ground, no success. Neither method results in a neutral light.

I then ran across this older thread that indicates the various resistance loads per pin on the neutral switch.
http://www.thumpertalk.com/forum/showthread.php?t=418404&highlight=neutral
After pulling mine off the bike and cleaning the pins with emry and contact cleaner I am getting very similar readings. This further supports the fact that the switch does more than just provide a simple ground to the instrument light as the neutral position is nearly an open circuit when measuring the switch off of the bike.

So my question is, how in the heck does this work? What am I missing to rectify the light issue?

Thanks for your help, knowledge and assistance.
Cheers,
Keith

 

[lairpost]

The bulb could simply be burned out. They are itty bitty but replaceable. I believe the are all the same, borrow the high beam bulb to test.

 

[kereams]

I opened the unit, they appear to be surface mount LED's that are soldered onto the PCB.

 

[Coffee]

I recently purchased a nicely used TE250 with an Athena 300 kit and all the goodies. Well maintained and documented. The only issue at all is that the neutral switch does not illuminate when in Neutral. As silly as it is, the wife really wants the light.

I have searched here and seen several threads for "Neutral Switch Issues" for the newer fuel injected bikes, but none related to the carbed bikes.

Looking at the circuit diagram (attached) in the manual one would assume that all the neutral switch does is provide a ground for the light circuit but it does not appear to work that way. Regardless of what gear or neutral I always have 12V between Pin #1 (Vbat +) and Pint #16 (Neutral Switch). I have tried opening the circuit, no success. I have tried jumping the Yellow/Green wire to ground, no success. Neither method results in a neutral light.

I then ran across this older thread that indicates the various resistance loads per pin on the neutral switch.
http://www.thumpertalk.com/forum/showthread.php?t=418404&highlight=neutral
After pulling mine off the bike and cleaning the pins with emry and contact cleaner I am getting very similar readings. This further supports the fact that the switch does more than just provide a simple ground to the instrument light as the neutral position is nearly an open circuit when measuring the switch off of the bike.

So my question is, how in the heck does this work? What am I missing to rectify the light issue?

Thanks for your help, knowledge and assistance.
Cheers,
Keith

Well, my initial guess would be a broken wire, but you sound like the type of person that would have looked for that.

I would take a pin/sewing needle/something sharp and poke it through the wire near the ecu which also goes to the switch. Measure the voltage from that pin/wire to ground with the motor running, with both the clutch and front brake pulled in, while changing gears. If the voltage changes then the sensor is doing it's job and the everything is working at the ecu.

Or just use the wire from the switch going to the display unit?

Some people have theorized that the ecu makes changes depending on what gear the bike is in, possibly the spark timing.

 

[kereams]

Thanks for the feedback. I will give that a try.
Cheers

 

[Coffee]

Let me know if you need more help. I have a 2006 TE250, but I'm the only one here at the moment and it will take 2 people to make the measurements. 1 person running the bike, the other one taking the measurements.

 

[kereams]

Awesome, thanks for your generosity.

I will get the measurements in the next few days and if things don't look as I think they should then I'll let you run the test to compare before I go off and buy parts.

 

[kereams]

Got my hands on a free workshop manual download over at KDRMotorsports. Here is the section for the GPS, unfortunately it mentions nothing about what it should be in Neutral.

 

[ramz]

unfortunately it mentions nothing about what it should be in Neutral.

Measurement A is for Neutral. The lazy 8 (8 on it's side) is the symbol for infinity. Infinite ohms will read as such on your meter, maybe with the same symbol.

 

[kereams]

Thanks!