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Update- months since the unsuccessful warranty repair attempt (they couldn't find the problem) TPS still tests good, but problem got so bad as to make the bike unrideable. Back in the shop for a second try at warranty repair. I got the mechanic to ride it while I was there dropping it off. Wow is all he said when he got back. Wish me luck. If they can't fix it with Yamaha's help, I'm ordering a TPS.

 
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Let me diagnose your failure. You have a failed dealer, you need to replace them with another OEM unit, you can do it without lube and no torquing is required.

Your FJR has a data Logging Mode in the ECU. When logging, the ECU monitors any engine sensor and logs the results as you ride. If the TPS is suspect the dealer can/should put your FJR in the data Logging Mode then send you out for a ride. When you return the dealer can use the View Log mode to look at the sensor performance. If it's bad, it will be right there in the data. With this powerful data logging tool there should be no mystery about any engine sensor or ES suspension issues.

 
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No doubt you're correct. Curious as to why that wasn't a step dictated by Yamaha, at least according to the dealer. They were very specific last time regarding each step they tried and were told to try by he mothership. May be a sign of the problem, if you know what I mean.

 
Directly from the book no real man would read, the FSM, "You can use the Yamaha diagnostic tool to identify malfunctions quicker than with conventional methods. By connecting the adapter interface, which is connected to the USB port of a computer, to a vehicle's ECU using the communication cable, you can display information that is necessary for identifying malfunctions and for maintenance to display on the computer. The displayed information includes the sensor output data and information recorded in the ECU."

Fault Diagnosis mode: Fault codes are recorded on the ECU are read, and the contents are displayed. The Freeze Frame Data (FFD) is the operation data when a malfunction was detected. This data can be used to identify when the malfunction occurred and check the engine conditions and running conditions when it occurred.

Logging Mode: Records and saves the sensor output value in actual driving conditions.

View Log: Displays the logging data.

 
Very much so. My dealer, which shall remain unnamed, gave me a great non-answer when I asked if they'd used the diagnostic tool and taken it for a drive. Their non answer was my answer. The shop and the mechanic have been great at communicating, great CS, just Not effective at fixing this particular issue. The mechanic called today and I asked him, since they and Yamaha know there's a problem, but can't find the cause, have they used the diagnostic tool and run the bike, then examined data afterward for signs of the problem. Mechanic was very measured- he said the on board diagnostic can't be used while the bike is being ridden. He knew what I meant. When I explained further, he was honest and said they didn't have one, and it was a bit of a delicate situation, couldn't discuss further. Good on him for being honest. They're still looking. Now- here's for the interesting part: I called Yamaha corporate. Said my dealer and shop are treating me great, but they can't find the cause of this problem, occurring with a Yamaha product, under Yamaha warranty, using a certified Yamaha mechanic and the Yamaha tech line. Yamaha's only response was- you can try another shop. No escalation, no nothing. There were more in depth conversations both with the mechanic and with the Yamaha rep that I won't share here. Most interesting factoid- despite a detailed recount (from the shop) of the things Yamaha said to check and paid to check on the Last unsuccessful visit for the problem, Yamaha tech line doesn't show any tech line contact for that visit. They show one months later, not close to either of the only two visits to the dealer the bike has ever had. Long story long- deciding whether to move to a different shop or gamble and change the TPS. Just proves the ion more correct. Dammit.

 
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If you have a volt meter (and know how to read it) you can diagnose the TPS with certainty yourself. You would back-probe the TPS connector with the meter then bungee, Velcro, duct tape or chewed bubblegum stick the meter to a location where you can safely see the meter while riding. Take whatever action provokes the issue while putting one eye on the meter. If the TPS is bad you will clearly see a voltage issue, no doubts, no guessing. If you chose this route and need additional help let us know.

Typically, a TPS fails bad in a very narrow rpm range or narrow separate ranges, but at the same rpm in any gear. The TPS is powered by the ECU using 0 and +5 volts. At idle the TPS will be around 0.720 volts, at cruising speed it will be 1.2 to 1.4 volts. When the TPS fails the voltage will drop back to 0.720 volts. The engine feels real rough because the ECU thinks your throttle movement has been idle, smoothly rising to cruising speed then abruptly back to idle and then abruptly back to an even faster cruise speed.

 
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Yamaha designed some pretty elegant diagnostic capability into these modern ECUs. It's a crying shame they will not supply the required tool on demand, or do not insist on the certified dealers obtain it on their own.

I suppose that the need to escalate the situation and press Yamaha US falls on your dealership. It is part of the bargain they make with the manufacturer when they take on a franchise that they will get factory support for their products.

Your experience and the complexity of the 3rd Gens especially with the electronic suspension is not giving me a arm fuzzy feeling about my own future.

 
Ion- this precisely describes my symptoms. Completely. It's why I've been pushing TPS replacement with the shop. I will have your recommended diagnostic done, one way or the other.

If you have a volt meter (and know how to read it) you can diagnose the TPS with certainty yourself. You would back-probe the TPS connector with the meter then bungee, Velcro, duct tape or chewed bubblegum stick the meter to a location where you can safely see the meter while riding. Take whatever action provokes the issue while putting one eye on the meter. If the TPS is bad you will clearly see a voltage issue, no doubts, no guessing. If you chose this route and need additional help let us know.
Typically, https://www.fjrforum.com/forum//index.php/topic/12074-anatomy-of-a-tps/?p=148013https://www.fjrforum.com/forum//index.php/topic/12074-anatomy-of-a-tps/?p=148013]a TPS fails bad[/url] in a very narrow rpm range or narrow separate ranges, but at the same rpm in any gear. The TPS is powered by the ECU using 0 and +5 volts. At idle the TPS will be around 0.720 volts, at cruising speed it will be 1.2 to 1.4 volts. When the TPS fails the voltage will drop back to 0.720 volts. The engine feels real rough because the ECU thinks your throttle movement has been idle, smoothly rising to cruising speed then abruptly back to idle and then abruptly back to an even faster cruise speed.
 
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Yamaha designed some pretty elegant diagnostic capability into these modern ECUs...It is part of the bargain they make with the manufacturer when they take on a franchise that they will get factory support for their products...Your experience and the complexity of the 3rd Gens especially with the electronic suspension is not giving me a arm fuzzy feeling about my own future.
Yamaha sez on their global web site:

Earning trust from our customersIn order for our customers to be able to enjoy our products safely and for a long period of time, we at Yamaha believe that the creation of a suitable environment of use is paramount. Service training is periodically provided to our distributors and their dealers who are our windows to the market place and our customers. Both the spirit and skill of service and maintenance are shared with our distributors in order to achieve customer satisfaction.

Service training aimed at distributors and dealersThe Service training comprises of dispatching service staff from Japan, local distributor Service training for new products, distributing service information, improving workshops, providing service tools, and practical/theoretical training.
Whether they actually do this or not.

After I get my Russell seat bill out of the way and get some new tires $$$ out of the way I will probably suck it up and buy the Yamaha Diagnostic Toy Tool for myself to play with and it will be available for NERDS use as well. I'm pretty sure we can figure it out and find some way to use/misuse the technology
smile.png
Wowzer, a $450 idle speed adjustment tool
wink.png


 
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I will provide further details privately, but let's just say my specificity during my calls to the shop and to Yamaha corporate resulted in a change. Not an instant one, but a change nonetheless. We are not the only ones now that know the YDT is a basic necessity, especially in my case. Dealer could not be more responsive in getting the things that need to be done, done at this point.

 
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Update- YDT data provided to mothership resulted in throttle body replacement being ordered. We shall see. I was convinced of TPS thuggery. Still am.

 
Glad to see that there is progress and it's based on real diagnostics.

Just one throttle body? What goes bad in a throttle body besides the fuel injector? Off to look at the FSM....

Good luck, hope this gets the goodness back!

 
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It was the pair. Thanks for the well wishes. (And for the info that I used to elevate the issue successfully).

 
Actually the TPS cost is peanuts compared to your purchase cost of the bike. Rather then all the hand wringing, etc, why don't you or the shop just put a new one in and be done with it. If that doesn't correct the problem then press on. But to play around with taped on multi meters and trying to interpret readings while riding just sounds like too much experimenting. Just my 2 cents worth!

Back to your regular programming!

 
But to play around with taped on multi meters and trying to interpret readings while riding just sounds like too much experimenting. Just my 2 cents worth!
1st choice is to have the dealer put the bike in the Data Logging mode. If the dealer won't/can't do this then the next option is the meter method. It's really not that big a deal and it provides proof positive if the TPS is the problem. The OP says he can reproduce the failure at will. One quick glance at the meter, reproduce the problem and he will immediately know if it is the TPS. The cost vs return vs time to perform is very good.

 
Assume you mean the "set" since all 4 are bolted together in one assembly.

And some good news for you, assuming they ordered part number 1MC-13750-00-00 (~$1300), which is the 49 state Throttle Body Assembly, they'll probably fix your problem since that includes the TPS along with everything else on the throttle bodies.

 
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