Speed Sensor Curcuit Malfunction

[DEcosse]

post image of the Diagnostic Screen on TuneECU with all the tabs on left margin open
(do ALT + Print Screen then 'paste' into a photo program and save image)

Also, while it's cranking, monitor the manifold pressure readings in the 'tests' screen and report what the three values are. (you MUST be at least cranking, if not actually running, to get these values)

 

[vocaldog]

post image of the Diagnostic Screen on TuneECU with all the tabs on left margin open
(do ALT + Print Screen then 'paste' into a photo program and save image)

Also, while it's cranking, monitor the manifold pressure readings in the 'tests' screen and report what the three values are. (you MUST be at least cranking, if not actually running, to get these values)

I'm hooking Tune ECU into an Android tablet. Not sure what diagnostic screen you mean. Do you mean error codes? I'll post pressure readings asap

 

[vocaldog]

post image of the Diagnostic Screen on TuneECU with all the tabs on left margin open
(do ALT + Print Screen then 'paste' into a photo program and save image)

Also, while it's cranking, monitor the manifold pressure readings in the 'tests' screen and report what the three values are. (you MUST be at least cranking, if not actually running, to get these values)

Pressure test reads at 960 on 1 &2 cylinders and 970 on cylinder 3. It's cranking at 275rpm. Speedo and tach hooked back up. Still getting 'speed sensor circuit malfunction' error code. But speedo connector has 2 pins broken off. I wonder if that's the source If all my problems?

 

[warp9.9]

Pressure test reads at 960 on 1 &2 cylinders and 970 on cylinder 3. It's cranking at 275rpm. Speedo and tach hooked back up. Still getting 'speed sensor circuit malfunction' error code. But speedo connector has 2 pins broken off. I wonder if that's the source If all my problems?

I would bet that would create a problem also.

 

[vocaldog]

I would bet that would create a problem also.

I guess it's time to find a used speedo. Prices on the new ones are ridiculous!

 

[vocaldog]

So does anybody know approx where the connector end of the speed sensor is? I figure I should check that, too.

 

[DEcosse]

Again - the speed sender issue will NOT cause any problem starting/running
You have something else causing the non-starting

But certainly if you have broken pins in the connector not much you can do about that & will have to replace speedo regardless

Pressure test reads at 960 on 1 &2 cylinders and 970 on cylinder 3.

That is virtually atmospheric pressure and no vacuum at all
Were those readings WHILE it was actually cranking? (& they did not change at all?)
(I haven't specifically tested it during cranking as opposed to actually running - so maybe if someone else with access can take a look and see what it reports)

 

[vocaldog]

Again - the speed sender issue will NOT cause any problem starting/running
You have something else causing the non-starting

But certainly if you have broken pins in the connector not much you can do about that & will have to replace speedo regardless




That is virtually atmospheric pressure and no vacuum at all
Were those readings WHILE it was actually cranking? (& they did not change at all?)
(I haven't specifically tested it during cranking as opposed to actually running - so maybe if someone else with access can take a look and see what it reports)

Thanks. Yes, that was while cranking. I'll definitely check all the vac hoses again! I'd love it if it was a quick fix like that!

 

[Kevin frazier]

You do not need the clocks connected (on a classic*) in order for it to start.
However that is indeed source of the 'speed sensor' error message you are getting - the power to the speed sensor actually originates from the gauge.
So now gauge connected means no power to the sensor means error detected by the ECU.
But that error will not prohibit anything regards to its ability to run
*different story on a CANBUS model i.e. Roadster or Touring.

So ignore the speed sensor error for now - it will be resolved when you reconnect working speedo gauge
And has nothing to do with ability to start or run.

When you say 'won't start' - what do you mean exactly?
Won't crank or won't fire?

If it is cranking over but won't fire, you need to look to whatever you might have done with your TPS & Stepper cal.
And also look to your hoses to the MAP sensor to be sure nothing leaking there.

hi decosse, can the speed sensor be bench tested, touring model?

 

[DEcosse]

... can the speed sensor be bench tested ...

You can connect 12V to power and ground then monitor the 'speed' signal wire - pass a magnet at gap of few mm across the face and you should see it change state high & low
(you can actually leave it connected electrically on the bike to do this if you like)

Other than what might be relatively obvious physical damage to the harness or connector I would be shocked to find a problem with one.