Intermittent speedometer...94 Civic w/ D15B7
 

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.

Thanks. https://honda-tech.com/forums/images...es/emdgust.gif

Re: Intermittent speedometer...94 Civic w/ D15B7
 

Reviving this thread-

seems a lot of us have this problem and after doing all the same troubleshooting procedures, problem cannot be solved.

Ive done everything that was done in the above thread, including replacing the VSS, cluster assy three times, a new ECU, ran my own wires to rule out a short in the wire harness

i plan to inspect the ign switch and fuse box next..

Re: Intermittent speedometer...94 Civic w/ D15B7
 

i 2 have this problem, but only after my tranny swap. when i spin the wheel my dmm only reads like 1v depending on how fast i spin it. the faster i spin the higher it goes but it never shows anything at cluster. like ida said when the speedo works the trip and odo work to. other than that everything is dead

Re: Intermittent speedometer...94 Civic w/ D15B7
 

well after some searching and rewiring i think its fixed (again).
https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/vss-wiring-pin-out-vss-wires-2321014/
picture is a bit misleading but correct
if standing on the passenger side looking into the bay over vss pin out from left to right is ground/power/signal
my vss is reading a 4.7 and is working

Re: Intermittent speedometer...94 Civic w/ D15B7
 

I have had similar issues on my 95' eh2 with the d15b7, I took the speed sensor out and my mechanic found that the ring that the speedo reads off of had separated from the diff itself, so it'd read whenever it caught on the diff. He said the plastic ring had melted off due to overheating. hope this helps anyone who still hasn't found any other issues.

Re: Intermittent speedometer...94 Civic w/ D15B7
 

Also, some have discovered that the solder attachment from the actual speedometer to the circuit board has cold solder joints.My 95 CIvic has this problem as well.I notice if the dash is in the sun and warm, it will register properly.But if it is cold (first thing in the AM) I have intermittent reading.