FJR repeatedly dies while riding at highway speeds

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I know you've refilled on gas but you never can be sure about getting all the water out of a tank. Just on an aside, I'd pull the tank and totally empty it into a spare lawn mower can and put verified clean fuel in it. Ya never know.

Either that or bust is right.....or is he left?

 
So, my interventions have started.....

First, I checked the battery terminal posts. Both positive and negative cables were tight. I pulled them loose, cleaned them nice and shiny, and re-assembled.

Next.... the handlebar kill switch.

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Housing was plenty clean..

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Contact points had a scant amount of tarnish but I cleaned them up anyway...

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Now the kickstand kill switch.

First the housing needs to be removed from the kickstand. This was easiest with removal of the two bolts that hold the kickstand in place then removal of the switch from the kickstand assy. The two mounting screws were held on with thread lock... making them a PITA to remove.

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There was some brown appearing grease present, but the contacts were generally clean and the internal springs were still pretty responsive. The contacts were cleaned, new dielectric grease was applied, and the switch was re-assembled. I also inspected the exposed wire cluster from this switch and found no integrity impairments for as far as I could track the wires.

Next.... lifting the tank and inspecting underneath. This may have to wait a few days due to work demand.

 
This reminds me of something my first bike did - it was an '83 or so Honda Nighthawk. It would randomly die - sometimes right after first stating up, sometimes a couple of hours later, sometimes not at all. But it got progressively worse.

I took it to get looked at - the issue turned out to be the ignition module. We swapped in a new ignition module and it ran fine.

 
...turned out to be the ignition module. We swapped in a new ignition module and it ran fine.
Are you referring to the Engine Control Unit 5JW-8951A-32-00, the Electronic Control Unit 5VS-85940-00-00, or the main switch (key switch) 5JW-82501-20-00, or either of the two ignition coils?

 
From the FSM:

ECU (Electronic Control Unit)

The ECU is mounted underneath the seat, below the toolbox. The main functions of the ECU are ignition control, fuel control, self-diagnosis, and load control.

The Engine Control Unit..... what does it do? I searched the FSM for "Engine Control Unit" and came up blank.

 
...turned out to be the ignition module. We swapped in a new ignition module and it ran fine.
Are you referring to the Engine Control Unit 5JW-8951A-32-00, the Electronic Control Unit 5VS-85940-00-00, or the main switch (key switch) 5JW-82501-20-00, or either of the two ignition coils?
The Honda that BG99 refers to had a pair of 'ignitor modules' which were stand-alone electronic ignition modules; this is not applicable to the FJR. The FJR has this function integrated into the ECU. In theory, if the FJR had an ignition problem there would be an error code stored in the ECU Fault History. Have you checked diAG code 61 to see if there are any faults stored?

 
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I went through the entire diAG system and found code 61 - cycled between 15, 21, and 30. This has never been cleared, so the 15 may have been when the TPS recall was done, 21... I'm not sure why code 21 (coolant temp sensor) other than maybe an issue when the valve clearance check was completed... and code 30 because I laid the bike down, activating the tip-over kill switch. The general summary of my findings and process of running through the diAG system are in post #4 of this thread. Any insight regarding my findings?

I'm about to head out to the garage and go through the ignition troubleshooting guide from FSM 8-9 through 8-13.

TTYL,

worldbound4now

 
Are you referring to the Engine Control Unit 5JW-8951A-32-00, the Electronic Control Unit 5VS-85940-00-00, or the main switch (key switch) 5JW-82501-20-00, or either of the two ignition coils?
Engine Control Unit 5JW-8951A-32-00 = ECU, the computer that controls fuel injection, load management, ignition and diagnostics

Electronic Control Unit 5VS-85940-00-00 = the ABS computer

 
Completed the ignition system troubleshooting process within the limitations of my tools (no dynamic spark tester) and all was OK except one spark plug wire had a little corrosion on it. I trimmed all wires by 1/4 inch and re-seated them into their respective plug caps. This shouldn't have been my failure issue since the FJR can run on 3 cylinders and my failure was an instant off, instant on scenario and not a sputter/misfire scenario. Both primary and secondary coils are within spec. The switches all test out during this testing phase.

The only sensor I did not test in the process is the crankshaft position sensor. The damn coupler is located in the middle of the bike, just below the throttle bodies. A CPS failure, if I'm correct, would lead to a mis-timed fuel injection type of issue.... so a sputter/misfire type of failure and not instant on/instant off issue. Also, a CPS failure should have generated an error code in the ECU. Unless informed otherwise, I'll leave the CPS out of my trouble hunt.

 
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Things I would be checking.

Battery leads both ends. My 05 acted similar. My GPS kept rebooting and the engine would die momentarily then restart. I tightened the battery cables and all is well.

Also fuel filter, vent, lines, pump.

 
There's a fuel filter on these things? :dribble:

edit: Hey, erik....glad yer going through this now so when it happens to me I can just call ya up and settle the problem with no work on my part and no thinking on my part what-so-ever. Hope you find the problem soon. Hate being with out a skoot.

 
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There's a fuel filter on these things? :dribble:

edit: Hey, erik....glad yer going through this now so when it happens to me I can just call ya up and settle the problem with no work on my part and no thinking on my part what-so-ever. Hope you find the problem soon. Hate being with out a skoot.
There sure is... you can see it here:

https://www.halllakeland.com/rex/fjr/pump.htm

 
Is it possible there could be a Faulty Fuel Pump Relay?

https://www.fjrforum.com/forum/index.php?showtopic=131192
When tested using the diAG system test, the fuel pump runs appropriately.
Well if it is intermittent with faulty contacts... it can Test Well but under a load may not perform correctly.

I feel for you and hope you find this dastardly cause.... which is same type of grief that led me to find the Main Harness Contamination problem... with NO Fault Codes.

Also make sure your Coil Wires are not shorting out:

https://www.fjrforum.com/forum//index.php?showtopic=126721&view=findpost&p=714281

May the force be with you!

 
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Just thought of something else that happened to me. If you have an additional Ignition Switch Relay installed, make sure it is NOT Loose.

I have one installed and when I would hit a bump, it would trigger the Relay to go OFF and the Bike would Shut Down. It would then hence start OK and do the same thing when a Bump came into the picture.

Once it was Securely Attached, it did not happen again. This is how I found Relays can be sensitive to bumps.

 
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Just thought of something else that happened to me. If you have an additional Ignition Switch Relay installed, make sure it is NOT Loose.

I have one installed and when I would hit a bump, it would trigger the Relay to go OFF and the Bike would Shut Down. It would then hence start OK and do the same thing when a Bump came into the picture.

Once it was Securely Attached, it did not happen again. This is how I found Relays can be sensitive to bumps.
To test out the shorting coil theory, I disconnected one coil at a time and started the motorcycle. The FJR, believe it or not, will run on two cylinders without stalling. In order for a complete power loss, both coils would have to fail at the same time.

I have not installed any extra relay off of the ignition switch, so that is out of the equation. Also, both of my failures were while riding on rather smooth paved surfaces. Great ideas though.

 
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