Why understanding Sensors is important

[Steve Cole]

TP or TPS is the result of what the throttle body is doing, it is important to remember "it's the result". So if your working with a cable bike the rider twist the handle bar mounted throttle cable and if its a ETC the rider used the Twist Grip to request from the ECM a different setting of the throttle body and the TPS measures the result.

[whittlebeast]

On the DBW bikes, what are the common modes of failure.  What is the trouble shooting procedure if you own a tuning system?  Just trouble codes or is there modes of failure the the ECU can't detect?

Andy

[harleytuner]

One of the most common problems I've seen with TBW bikes is high idle.  Improper shut down is a culprit. It it's important to shut off the bike using the ingnition south and not the run/stop switch. As already pointed out the voltage between TG 1&2 must always be 5 VDC. If you use the run/stop switch it does a soft shut down of the systems and it's possible that TG 1&2 can be in a transition state and not be 5VDC between them. Next time the bike starts it will default back to where it was shut off and that's what causes high idle. Sitting off with the ignition switch is a hard kill, all the bikes systems shut off instantaneously.

I guess the important thing to know is we are turning off computers now. And just like out computers at home, there is a proper way to do it.

[UltraNutZ]

IMO since you asked Chad.. lol

I don't understand why the issue still persists.  HD spends more time worrying about stupid BS like "infotainment" than trying to resolve some of these electronic issues.  It's not difficult to code into the ECM a reset command signal sent to and received from the TGS at every ignition-on sequence, problem solved.  Nope, too damned worried about Boom Audio...

[Buglet]

    On the cam bus bikes does the bar switch turn off the ing or fuel. Another thing is if you turn of the bike with the bar switch the engine will stop running but the rest of the bike will stay on untill the back wheel comes to a complete stop. Must be the safety police looking out for us.

[joe_lyons]

    On the cam bus bikes does the bar switch turn off the ing or fuel. Another thing is if you turn of the bike with the bar switch the engine will stop running but the rest of the bike will stay on untill the back wheel comes to a complete stop. Must be the safety police looking out for us.

The run switch has 2 operations for off.  There a can signal for off and there is a hard shut off.  That's what the 5th wire is for on the right side.

[Buglet]

    I forget to include to say if you also turn off the main switch everthing still stays on untill the back wheel comes to a complete stop.

[joe_lyons]

One of the most common problems I've seen with TBW bikes is high idle.  Improper shut down is a culprit. It it's important to shut off the bike using the ingnition south and not the run/stop switch. As already pointed out the voltage between TG 1&2 must always be 5 VDC. If you use the run/stop switch it does a soft shut down of the systems and it's possible that TG 1&2 can be in a transition state and not be 5VDC between them. Next time the bike starts it will default back to where it was shut off and that's what causes high idle. Sitting off with the ignition switch is a hard kill, all the bikes systems shut off instantaneously.

I guess the important thing to know is we are turning off computers now. And just like out computers at home, there is a proper way to do it.

I thought this was taken care of in the cals and talked about in TT380?  Ecm keeps powered up for 10 sec after run switch is killed.

[harleytuner]

One of the most common problems I've seen with TBW bikes is high idle.  Improper shut down is a culprit. It it's important to shut off the bike using the ingnition south and not the run/stop switch. As already pointed out the voltage between TG 1&2 must always be 5 VDC. If you use the run/stop switch it does a soft shut down of the systems and it's possible that TG 1&2 can be in a transition state and not be 5VDC between them. Next time the bike starts it will default back to where it was shut off and that's what causes high idle. Sitting off with the ignition switch is a hard kill, all the bikes systems shut off instantaneously.

I guess the important thing to know is we are turning off computers now. And just like out computers at home, there is a proper way to do it.

I thought this was taken care of in the cals and talked about in TT380?  Ecm keeps powered up for 10 sec after run switch is killed.

I believe you are correct Joe, but since we are talking sensors and not tuning I figured it's worth mentioning.  HD has corrected the problem on the newer canbus bikes that only have the handlebar switch.  But there's a lot of bikes out there still running stock calibrations or PC's that still have this issue.  Last time I wrenched/tuned at a dealer was in '08 so if HD came up with a software upgrade for this problem with DTII it was after I left the dealer and went to the INDY.

[Steve Cole]

The issue was solved back in 2009

When looking at it from the sensor level nothing at all changed. Also we should add the Run/Stop switch as a sensor as well as all the other switches to the list of important sensors.

[harleytuner]

The issue was solved back in 2009

When looking at it from the sensor level nothing at all changed. Also we should add the Run/Stop switch as a sensor as well as all the other switches to the list of important sensors.

That still leaves 08 TBW bikes that can still possibly have that issue.

Steve, what about 09 bikes running the same calibrations as the 08 bikes?

[Steve Cole]

All the calibrations for ETC bikes were upgraded in ~ mid 2009 year. So any bike that has the calibration updated along the way has it resolved. It was nothing more than a simple adjustment in the calibration. Since the ECM is learning all the time by leaving the TGS turned slightly after the Run/Stop switch was switched off it learned a new offset. The calibration waited a length of time before it took the necessary reading from the TGS after the Run/Stop switch was turned Off. The fix was adjust the timer to a slightly long wait period, so the the consumer had released the TGS. By teaching consumers to release the TGS and switch the bike off with there right hand, all we did was force them to let go of the TGS so it could return to its idle position. Then the ECM could take the reading it needed without the TGS being slightly twisted from there hand.

[Just Nick]

What sensor is next Steve?