Throttle position sensor

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Have had no error codes show up on my 04' with a PCIII installed.
Ditto. Check your connections RTR, you may have a couple crossed.
there is only one way to connect the pc (plug it in) what is RTR ?????? Bike runs to kill for, couldn't be happier thanks for the reply.
I speak Radese.. let me translate... RTR = RonToRide :)

Maybe it's a loose connection...? Did you tape over your O2 sensor connectors after disconnecting them? What side of your mouth are you holding your tongue in?

 
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Have had no error codes show up on my 04' with a PCIII installed.
Ditto. Check your connections RTR, you may have a couple crossed.
there is only one way to connect the pc (plug it in) what is RTR ?????? Bike runs to kill for, couldn't be happier thanks for the reply.
I speak Radese.. let me translate... RTR = RonToRide :)

Maybe it's a loose connection...? Did you tape over your O2 sensor connectors after disconnecting them? What side of your mouth are you holding your tongue in?
YI think I just swallowed my tongue. I did not tape over the 02 sensors but will now. thanks

 
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Theres only one way to install a water pump, doesn't mean I haven't seen people give up after the 4th try (finally brought it to our shop, real story). People force connectors to mate all the time, it helps keep techs busy, along with all the other fun stuff we find. Just a thought, have you reset the TPS to work with the PC? On the Dynojet website for the PC, the instructions are clear and easy to follow.

 
reset the tps to work with the pc on the dynojet website. Yes is is simple but did not turn off the engine code 15. Think I will just ride it as it runs so well. thanks again

 
reset the tps to work with the pc on the dynojet website. Yes is is simple but did not turn off the engine code 15. Think I will just ride it as it runs so well. thanks again
Rethought this over lunch. A 15 is a TPS open or shorted condition. Do a diagnostic on the display, and follow code 62 operation to clear the code. It may have set and is whats keeping the light on even though the condition is no longer present. If you were able to set the TPS up via the PC software, then it's working. I also assume you have checked it's range via the diag screen.

 
rontoride sez:

Installed a pc111usb today...Did a TBS also. Now the engine trouble light stays on all the time with a diag. code of 15 showing...Was wondering if the PC takes over the TPS position as on the computor it showed 0. Trying to diag it showed 101 on top and 0 on bottom of screen with no change at all with any throttle movement. Seems like the pc has taken over. It sure runs great except for the engine light being on. Help anyone?????
What Rad said. Plus -- you have already seen your diAG screen show the TPS as 0 - 101. Normal is ~15 to ~97 so your TPS is out of range. Before delving into the following BS, follow Dr. Rad's advice and reset the error code. If you pop the Check light again then proceed.....

The Power Commander does not have anything to do with the ECU reading the TPS. The PC does offer a TPS like setting that matches the PC response to the throttle but it is independent of the ECU. The PC does not communicate with the ECU in any way, the PC sits on top of the fuel injector signal and modifies the injection pulses.

The ECU supplies GND and +5 volts to the TPS. Picture a resistor with 5 volts on one end and ground (0 volts) on the other end. At idle there is a contact (wiper) touching the resistor *almost* on the ground end of the resistor. As you twist the throttle the contact slides up the resistor toward the 5 volt end such that the voltage climbs linearly as the throttle is twisted. The ECU does a conversion so that 0 volts = 0% throttle and 5 volts = 100% throttle. At idle you need a bit of throttle to keep the engine running -- which is the throttle stop adjustment. When you see 15 on the diAG screen you are seeing 15% of the 5 volts or .75 volts on the wiper of the potentiometer (the resistor) at 50% there is 2.5 volts on the wiper at 97% there is 4.85 volts on the wiper.

Your diAG screen shows 0% and 101% which is not acceptable. You need to check the TPS and see that one wire is truly 0 volts; one wire is truly 5 volts (a reference voltage put out by the ECU) and observe the voltage on the third wire follows the throttle opening with a range of .75 volts to 4.85 volts.

 
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Wow Ion... I learn something new every day coming in here... not always a good thing, but I'll count that description/explanation in the plus column... :thumbsup:

 
rontoride sez:
Installed a pc111usb today...Did a TBS also. Now the engine trouble light stays on all the time with a diag. code of 15 showing...Was wondering if the PC takes over the TPS position as on the computor it showed 0. Trying to diag it showed 101 on top and 0 on bottom of screen with no change at all with any throttle movement. Seems like the pc has taken over. It sure runs great except for the engine light being on. Help anyone?????
What Rad said. Plus -- you have already seen your diAG screen show the TPS as 0 - 101. Normal is ~15 to ~97 so your TPS is out of range. Before delving into the following BS, follow Dr. Rad's advice and reset the error code. If you pop the Check light again then proceed.....

The Power Commander does not have anything to do with the ECU reading the TPS. The PC does offer a TPS like setting that matches the PC response to the throttle but it is independent of the ECU. The PC does not communicate with the ECU in any way, the PC sits on top of the fuel injector signal and modifies the injection pulses.

The ECU supplies GND and +5 volts to the TPS. Picture a resistor with 5 volts on one end and ground (0 volts) on the other end. At idle there is a contact (wiper) touching the resistor *almost* on the ground end of the resistor. As you twist the throttle the contact slides up the resistor toward the 5 volt end such that the voltage climbs linearly as the throttle is twisted. The ECU does a conversion so that 0 volts = 0% throttle and 5 volts = 100% throttle. At idle you need a bit of throttle to keep the engine running -- which is the throttle stop adjustment. When you see 15 on the diAG screen you are seeing 15% of the 5 volts or .75 volts on the wiper of the potentiometer (the resistor) at 50% there is 2.5 volts on the wiper at 97% there is 4.85 volts on the wiper.

Your diAG screen shows 0% and 101% which is not acceptable. You need to check the TPS and see that one wire is truly 0 volts; one wire is truly 5 volts (a reference voltage put out by the ECU) and observe the voltage on the third wire follows the throttle opening with a range of .75 volts to 4.85 volts.
Well thanks to all the help it is working ok now. I had noticed that the fuel guage when I installed the pc was on three lines. Shortly after test riding the bike I noticed that in had one bar flashing?????I read in the manual that if you run out of gas the engine light will come on also and not go off. I started from scratch and disconnected all the connections from the pc to the ecu and reconnected them making sure they were all the way in. Vola, no more light and three bars on the fuel guage. I surmise that a poor snap in connection read the fuel tank as empty turning on the light just like a tps problem. Thanks for all the great advice, will see you helpful fellows in Reno......btw thanks again for explaining how the tps works the voltage up and down. after reading that I consider myself a smarter fellow????????16 to 100 now on the diag screen.

 
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FYI... Thanks all... Mine is in for TPS transplant today, should have it back tomorrow, I will let everyone know how this has resolved or not resolved my issues with surging...

Thanks, FYI... 2003 FJR - commuter bike, so I spend alot of time in the low rpm range in traffic, 15.7k miles on it.

 
The dealer said he checked them and there was no errors but am still having problems with it surging.
The dealer will have tested the TPS per the manual which simply says read the TPS and idle and full throttle. This only checks for a catastrophic failure. You need to check the area of the sensor inbetween these two positions.

Checking the TPS Sensor

This test is done using the Diagnostic screen. How to:

With the key off, press and hold the "Select" and "Reset" buttons simultaneously and turn the key on (do not start, just ON), continue to hold the buttons until the display next to the fuel gauge says diAG (5-10 seconds).

Release the two buttons. Now, press the "Select" and "Reset" buttons simultaneously again. After ~ 2 seconds the display should show d1:01 on top and a two digit number at the bottom. You are now looking at the throttle position sensor (TPS) output. The TPS value is the two digits at the bottom of the display.

Turning the throttle will change the digits. Normal is 15-17 with the throttle closed and 97 to 100 with the throttle wide open. When the TPS goes bad it can be catastrophic, where the two digit value is just plain wrong and doesn't follow the throttle at all. This could be the TPS, it could be in the harness that connects to the TPS or it could be the ECU.

The other failure mode of the TPS is to have 'dead spots' as the throttle is opened. This is the most common failure and it usually occurs at roughly 20-40% of throttle opening because that is range where the throttle is positioned for most riding. To check this -- very, very slowly open the throttle from full closed to full open and observe that the numbers climb with no skipped numbers and no drop-out readings (e.g. 45, 46, 47, 01, 01, 48, 49) The 01 reading is a 'drop-out'. This failure is almost certainly the TPS.

To leave the diAG mode simply turn the key off. Done.

Alan
Took a ride in NH/VT/MA Thursday and the bike kept cutting out and even stalled at a stop. I had to shut turn key off and on to get the thing to idle.

I did the diagnostic routine and it starts at 18 and then drops a couple then drops to 5 then picks up and drops off again when it was in the 20s

I guess I'd better do the tps recall eh?

 
Sure sounds like classic TPS failure. The readings drop out right in the idle/light throttle area, just where you are experiencing the problem. Time to see a dealer.

 
Sure sounds like classic TPS failure. The readings drop out right in the idle/light throttle area, just where you are experiencing the problem. Time to see a dealer.
Appointment made! Makes me feel better knowing it's probably a free and easy fix. Thanks for posting all that info!

 
I had a TPS problem with my '03. It was hard to figure out what was wrong. the dealer you take the bike to can make all the difference. I caried mine to one dealer who sat on my bike for 2 or 3 days doing nothing because he was waiting on a call for the Yamaha techs. I quickly grabbed the bike from him before he could do any damage. I carried it to another dealer who quickly agreed I had a problem. They replaced the O2 sensor first, but that didn't cure the symptoms. The TPS was the culprit.
I had no recognizable symptoms at highway speeds, but tooling around city streets it would run really rough and often stall altogether if the revs got too low.

When you think you're bikes got problems, be persistent and keep plugging away until you get it fixed.
Scott. I have those symptoms with my 03. I followed the diagnostic procedures as Allen posted and the TPS checked ok on a cold motor. Mine seems to get worse when the engine warms up. I will do the TPS Diag again with a warm engine. Everthing works ok at highway speeds. I guess the FJR was meant to go fast. I could have other problems but can't afford the Yamaha shops labor charges. I hope when I check it warm it fails. It's an easy fix with the exception of the lower screw. Have a good day and ride safe.

 
I recently got an 07 ABS.. test ride was fine and it was smooth. I got it and the second day onwards got the same problem. Engine is very jerky between 1500 to 3000 RPM range. Idle is set at 1100. is this problem seen with an 07 also? :unsure:

 
I recently got an 07 ABS.. test ride was fine and it was smooth. I got it and the second day onwards got the same problem. Engine is very jerky between 1500 to 3000 RPM range. Idle is set at 1100. is this problem seen with an 07 also? :unsure:
Hmmm... Am I the only one with this problem...

Anyone???

 
I recently got an 07 ABS.. test ride was fine and it was smooth. I got it and the second day onwards got the same problem. Engine is very jerky between 1500 to 3000 RPM range. Idle is set at 1100. is this problem seen with an 07 also? :unsure:
Hmmm... Am I the only one with this problem...

Anyone???
That's (approx.) 27 ~ 55 MPH (in top gear).

I'm usually in 3rd gear at those speeds.

I wish I could help with your problem: "jerky engine" -- but I guess I never ride at those RPM? :unsure:

 
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