Sensor light on!!!

[Cheesemaker]

I don't know if any of you have any knowledge to help me on this but it's worth a try!?!?!?  I own a 85 nissan 4x4, i know it's not a toyota, but it has been trouble free for the last ten years, the only problems have been inflicted by it's owner.  I have a sensor light on in the dash, i've been told that it goes on every 25,000 miles after it reaches 100,000 miles.  I've had it reset twice by a mechanic that is no longer in town.  And all the other mechanics don't want to deal with it.  I've called nissan and they won't tell me what to do to fix it!!  But, if I bring it in they will do it for a fee!?  First of all, the closest nissan dealer is over a two hour drive one way!!       I've just let it go for the last year, but now it's starting to flicker and affect the other dash lights.  I know it's just a simple thing to do.  Haynes and chilton books don't say anything about it!!  Please help, i just don't want anything to short out in the dash! 

[Rockcrawlintoy]

have u tried disconnecting the batteryfor 30 seconds.

Drew

[Cheesemaker]

Yes!! and while disconnected, I stepped on the brakes to eliminate any stray electricity out of the brain!
I've been told that there is a button up in the dash somewhere, I have spent many hours looking for it, I've almost torn the hole dash apart looking!!  The brain is under the driver seat!  but it has no switches or wire disconnects!  I'm frustrated, it's probably something that's very simple that i'm overlooking.  But I've tried everything and then some, my wife just wants me to drive my POS of a cliff!! 

[guywithuglyyota]

Well for older toyotas there is a very small switch located near the dead pedal area near the clutch pedal. You turn the ignition on, cycle the switch and the light goes off. Its basically a reminder to change your 02 sensor. On Yotas its white, about the size of a sharpie pen cap. Keep in mind it will most likely be cleverly dusguised so the average joes like us cant just go about ignoring emission warnings