For awhile now my speedo has been intermittent....it usually stays stuck on zero, but occassionally comes to life for temporary bursts often quivering and jerking a bit, but then falls back to zero. When speedo doesn't work, odometer & trip meter don't register mileage change, but when speedo does work, miles advance. Car has ~133k miles. No CEL or fuse blowing is occurring.
Went to junkyard and got another cluster and VSS top portion (so not 100% sure either is absolutely good). Replaced cluster...no change, still doesn't work. Replaced VSS top portion....no change, still doesn't work. Inspected VSS lower stem that goes into tranny...looks good: driven gear shows no wear no particulates clean sharp gear edges, part is totally mechanical so not much to fail...looked into tranny & can see differential gear that drives speedo and it turns when tire turns, so lower stem & tranny look good. Think maybe it's electrical/wiring, so attach rope to main wiring bundle that VSS goes into and feed rope through window & into car. Drive around yanking rope, but speed doesn't show any intermittency or come to life at all.
Forced to resort to debug procedure in Honda Service manual pg 23-140/141 for "Speedo/Trip Meter/Odometer Troubleshooting". Start by testing continuity & voltages appearing at VSS sensor connector. Everything OK until step: "Measure voltage between VSS plug yellow/white wire pin and ground....Is there APPROX 5V OR MORE?". How much is "APPROX 5V". Mine reads 4.7 V...that's "approx 5V" BUT it's not MORE???????? so what's the call...OK or not?????? Can someone out there with a working speedo please pull that VSS connector and measure yellow/white voltage-to-ground and tell me what you get ????????????????????? Measure it with ignition key 'on' (but not all the way to start...car doesn't have to be running).
Oh, and better yet if anyone has had these same symptoms & solved the problem, please let me know what fixed it.