Symptoms, At 30mph, speedo goes out, left turn signal works, speedo comes back on blinking, right turn signal steady no blink. T-Minus 2 weeks to glacier and the speed has a problem, 99 Heritage EVO, Under 30 mph speedo does come back on. I had to fix the ground lead on my right headlight it pulled from the casing I sealed it back in there wrapped around the ground with the silver plumbers tape. So any ideas on this will be great. I do have elec test kit, and manual.

 

Verified ground on right headlight, and the ground is good to go. I am now looking for the wiring mount it is not on the tires, where is the speedo attached?

 

pretty sure at this point basd on power that it is the sensor unit.

 

Well, we have to assume you found out that your speedometer is connected to a speed sensor on you transmission.

Easiest way to check this is to connect a volt meter to the speed sensor and look for pulses when the bike is moving. Unfortunately since yours works up to 30mph and then quits, this might be difficult to see at this speed unless you use a scope instead of a multi meter. I believe that on your bike the VSS signal actually goes to the PCM, not directly to the speedo, but I may be wrong. If that's the case, using a real time scanner for the PCM will show you what it is outputting.

 

thanks for the response, yes, the unit is on the transmission, I cleaned the shavings off and I have to clarify, at some RPM level is when it turns off, the speed is noticeable then it fluctuates and turns off, I am going to check my voltage regulator, but I just replaced that last year. But the speed works fine at 20-25 mph turn signals work lights work no problems. I am pretty convinced the sensor unit is bad, but I will place in nuetral and can replicate the issue at higher RPM, I will test the voltages tonight, what values am I looking for 12 volts? what is the voltage for the sensor...? Thanks again !!!

 

If it's more RPM related than speed then I would look more towards a loose connection that is affected by vibration. Unfortunately, this could be a loose connection inside of a piece of electronics such as your speed sensor or your speedometer.

As far as voltage, most speed sensors are running at 12 volts. The actual signal is a pulse that changes with the speed of the bike. That's why it's easier to diagnose with a scope than with a multi-meter. Checking with a multi-meter is good for telling if you're getting nothing but since you're intermittent based on speed or RPM, using a multi-meter prolly won't tell you a lot.

A stealer can test the speed sensor for you. This might be less expensive than buying one and finding out that it isn't the problem. I would assume they'd hit you for a half hour or an hour for the diagnostics. Then you could do the repair yourself. I'm not a big fan of letting someone else work on my vehicles, but sometimes they have better diagnostics equipment than is practical for us to have on hand at home.

 

Well I saw the other speedo issue on the forum, so I just ran the rpm test at the battery and got 18+ volts at higher rpm? Is this normal(THIS IS NOT NORMAL), I do not have a manual in front of me...the speedo dies at about 14 volts.....Okay read the manual, this is the problem...Ordered a new regulator from debrix.com 59 with shipping.

UPDATE: Purchased cd manual from buildahog? Received new regulator (chrome) 59.00, replaced circuit breaker as well 7.00, ordered new spark plug wires 28.00. I could not believe the difference in the bike as well as performance, the plugs were fouled replaced with 3.00 champions and this became obvious once the new regulator was in I am at the proper voltage and the speedo is working. Oh got 53mph over a 220 trip ride air temp was 80-95 degrees.... I still need to replace old battery cables which I intend to do on the winter maintenance. Hope this helps