Bike: 2007 TE 250 Do the pickup wires for the speedo/odo have any power running thru them, or do they just act as a loop, in conjunction with the pickup mounted to the brake caliper, to count the number of times the magnet goes past the pickup? My speedo/odo stopped working on Sunday, but everything else seems functional on the computer. I suspect that the speedo/odo wires have broken inside the insulation, given the zillions of times they flex near the handle bars. Are there any other issues I should look for when I tackle this?
Usually the pickup sensor is a reed switch that closes it's contacts when close to the magnet. You should be able to test the sensor while disconnected with a ohm meter. The resistance should drop to near zero as the magnet passes by. http://en.wikipedia.org/wiki/Reed_switch Also you can use a jumper wire to periodically short together the pins on the connector going to the odometer. This should simulate the pickup sensor.
You are correct in stating the pick up wires are a loop....and the polarity does not matter.... black and blue wires at the instr. cluster......hook up across the harness side ...switch your meter to AC volts and spin the tire...if its working you will generate 1v..... if its ok...your wires and sensor are fine
Troy your probably right about the AC voltage. The pickup could be an inductive coil rather than a reed switch. The coil will produce a small AC voltage as the magnet passes by. Good call
Troy- Forgive me for my electrical troubleshooting naivete- Do you mean that I should insert the meter probes into the small connector attached to the wires that are coming from the pickup? Or jumping across one of the wires, in effect completing the loop? I haven't had a chance to dig into it yet(hope to tonite), but suspect a bad wire or two, as the speedo started working intermitently and giving some unusual readings(reading way higher or lower than actual speed) before quitting altogether. Thanks Slowpoke
Problem was found fairly quickly when I got at it last nite; broken wire near the connector behind the speedo/computer. All fixed and working good.
