2000 honda accord speedometer not working

Hello Mates!

i have a 2000 honda accord ex coupe 3.0 that the speedometer, tip and odometer are not working. The computer is reciving the signal frome the Countershaft Speed Sensor and i can monitor the Vehicle speed on the Scanner.
I'm backprobing the signal wire from the PCM at the Instrumental Cluster witch is a BLU/WHT Connector B Terminal 2.

The voltages i'm getting is 4.22V with Ignition On Engine Off and it produces a square signal while driving.
The interesting thing is that the Voltage is still stays with the Key Off for 10 seconds or so and when i opened the door the Voltage comes back
Anyone have any idea what kind of signal i'm suppose to get and also if the voltage it suppose to be there?

Hey jaivs26! I think you're looking at a bad instrument cluster. From experience, the signal you're seeing at pin B2 of the instrument cluster is exactly what you're supposed to be seeing. The cluster provides the voltage, and the PCM grounds it to produce the needed signal. Since you're seeing a square wave, I'd say the PCM is doing its job.

From the wiring diagram, it looks like that circuit isn't shared anywhere else, so I think you're good to go on a cluster. Maybe verify powers and grounds at the cluster just to be sure.

Hi: Tyler
i got a known good cluster but still the same issue!
i check the powers and grounds and seems ok

Maybe a pin fit issue? As above I'd say if you have a good square wave then you've got your signal. Did your cluster work in the vehicle you swapped clusters with ?

Anyone got the picture of the diagram? fancy a gander

Hi: Rick
i can't test my cluster because i don't have the car with me.. i got the cluster from my friend he has the engine out at this moment.

Here are some screenshots i got jut right now the only thing i noticing is the computer is not pulling the signal all the way to 0v
is it normal?
this is the signal at the cluster B2



and this is the signal at the countershaft speed sensor

Hello guys I'm back with and update

The problem was the ECU it wasn't grounding the signal all the way to 0. volts and that's way the cluster didn't work
i'm going to put few screenshots of the before and after readings at the cluster.
this is the bad signal

and this is the good siganl


By the way for all DIY community the ECU needs to be programmed. I programmed mine with the AUTEL maxiDAS DS 708

Nice fix, it reminds me of another car with a speed sensor fault and I did a bypass test pulling the signal wire voltage down with a test light.
I used a led test light first and it didn't work, it wasn't pulling the voltage low enough
Then tried an incandescent and it worked fine

Thanks for reporting back with the fix!

Maybe I should have asked about the specifics on the waveform earlier on? :blush: Speaking of, it looks like the ECM is varying how far down it's pulling the signal. The Verus capture shows it going down to 2-ish volts, but the Vantage shows about 4V. :blink: