'04 '05 ABS Motor Fuse

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
My Gen I behaved exactly as specified in the manual.

To read the manual at the fundamental level it offers four troubleshooting sections.

The first section is ABS self-diagnosis (past malfunction) performed via the error code method.

The second section is ABS self-diagnosis (present malfunction) performed via the error code method. This is supposed to be a comprehensive reading of the ABS ECU and all associated electrical signals, sequence of events and confirmation that some actions took place when commanded. This is not a comprehensive hydraulic unit test.

The third section is Hydraulic Unit Operation Test 1 which should verify that the spool valves, metering and fluid flow is correct. This test generates the same reaction-force pulsating action that is generated in the brake lever and brake pedal when the ABS is activated. David's FJR fails this test.

The fourth section is Hydraulic Unit Operation 2. This test checks the function of the ABS after the system was disassembled, adjusted, or serviced.

Since David's ABS has no codes and fails the hydraulic test and has no rear brake ABS it doesn't look good for the hydraulic block. The only error the electronics can see as the result of a hydraulic failure are four situations in which there is Brake Dragging. There are no codes associated with failure of a wheel to release after the brakes were applied in a manor that should have triggered the ABS.

* All text is blue is quoted from the FSM.

 
Last edited by a moderator:
My Gen I behaved exactly as specified in the manual.

To read the manual at the fundamental level it offers four troubleshooting sections.

The first section is ABS self-diagnosis (past malfunction) performed via the error code method.

The second section is ABS self-diagnosis (present malfunction) performed via the error code method. This is supposed to be a comprehensive reading of the ABS ECU and all associated electrical signals, sequence of events and confirmation that some actions took place when commanded. This is not a comprehensive hydraulic unit test.

The third section is Hydraulic Unit Operation Test 1 which should verify that the spool valves, metering and fluid flow is correct. This test generates the same reaction-force pulsating action that is generated in the brake lever and brake pedal when the ABS is activated. David's FJR fails this test.

The fourth section is Hydraulic Unit Operation 2. This test checks the function of the ABS after the system was disassembled, adjusted, or serviced.

Since David's ABS has no codes and fails the hydraulic test and has no rear brake ABS it doesn't look good for the hydraulic block. The only error the electronics can see as the result of a hydraulic failure are four situations in which there is Brake Dragging. There are no codes associated with failure of a wheel to release after the brakes were applied in a manor that should have triggered the ABS.

* All text is blue is quoted from the FSM.
As far as I can tell, I pass test 1. Pulsations occur. Test 2, however, fails to return the pedal to the resting position despite feeling pulsations. I agree that it looks like the hydraulic unit at this point. I'm going to keep trying the tests and the tapping, just to see if it can be freed up, but I am not too hopeful.

Maybe I'll try temperature changes like heat or dry ice while tapping on it and doing the tests...nothing to lose...unless it ISN'T the block and I manage to bugger it up.

 
Last edited by a moderator:
David,

It's actually starting to sound like an ABS ECU problem. If you were nearby I would volunteer to swap ABS ECUs with you to test it. Maybe there is another 1st gen ABS guy nearby that will be willing to help you out?
There IS something you or someone with a gen 1 bike with working ABS could do that would help me a lot: I'm curious if the failure of the pedal to return to the resting position in hydraulic unit test 2 means there is a blockage in the hydraulics in my bike, or if that is just normal. Seems like either the signal from the ECU to the solenoid is bad or there is a stuck valve.

OK, I just re-ran these tests on my '05. I could not remember how vigorous the pedal action was on either test, which was why I would not commit to yours being a failure. I am sorry to report that it is.

When I plug the jumper in, kill switch to off and turn on the bike on for test 1, the ABS light comes on for a bit then immediately begins flashing at intervals of 1/2 second on 1/2 second off. This says I have no stored codes.

Push the starter button for 4 seconds then actuate both brakes and the pulsation on the lever, pedal lever is equally vigorous on each.

Same thing for test two, turn the bike ignition on with both brakes applied and the return to home is equally vigorous on both the lever and pedal.

I'm afraid that this does suggest that your hydraulic unit is where the problem is.

I still don't get why you don't get a code 42. That would seem to describe this condition exactly (unless I'm reading it wrong).,

 
I still don't get why you don't get a code 42. That would seem to describe this condition exactly (unless I'm reading it wrong).,
Code 42 = Brake dragging = Rear wheel will not recover from the locking tendency even though the signal is continuously transmitted from the ECU (ABS) to release the hydraulic state.

[speculation] The dragging must occur with a duration longer than some specified time or distance. One quick tire chirp may not be enough to set the code.

Glad to see that your ABS is working! It had to be good for your brake system to move fluid through the spools.

 
David,

It's actually starting to sound like an ABS ECU problem. If you were nearby I would volunteer to swap ABS ECUs with you to test it. Maybe there is another 1st gen ABS guy nearby that will be willing to help you out?
There IS something you or someone with a gen 1 bike with working ABS could do that would help me a lot: I'm curious if the failure of the pedal to return to the resting position in hydraulic unit test 2 means there is a blockage in the hydraulics in my bike, or if that is just normal. Seems like either the signal from the ECU to the solenoid is bad or there is a stuck valve.

OK, I just re-ran these tests on my '05. I could not remember how vigorous the pedal action was on either test, which was why I would not commit to yours being a failure. I am sorry to report that it is.

When I plug the jumper in, kill switch to off and turn on the bike on for test 1, the ABS light comes on for a bit then immediately begins flashing at intervals of 1/2 second on 1/2 second off. This says I have no stored codes.

Push the starter button for 4 seconds then actuate both brakes and the pulsation on the lever, pedal lever is equally vigorous on each.

Same thing for test two, turn the bike ignition on with both brakes applied and the return to home is equally vigorous on both the lever and pedal.

I'm afraid that this does suggest that your hydraulic unit is where the problem is.

I still don't get why you don't get a code 42. That would seem to describe this condition exactly (unless I'm reading it wrong).,
Thanks, very nice of you and Ionbeam to do that and I appreciate it. You guys are fantastic.

I also tested the voltage coming from the ECU to the solenoids and got 12+ front and rear, so it almost certainly isn't the ECU. Moreover, when I disconnected the coupler I got fault 31, "no connection to hydraulic unit solenoid coupler" (or something like that). Looks like frozen spools. ****. Before I try to replace it myself, I'm going to take it to the dealer to see if they can get Yamaha to help out with the replacement. Chances are slim, but worth a try.

 
Last edited by a moderator:
Best-Of-Luck-2.jpg
 
I still don't get why you don't get a code 42. That would seem to describe this condition exactly (unless I'm reading it wrong).,
Code 42 = Brake dragging = Rear wheel will not recover from the locking tendency even though the signal is continuously transmitted from the ECU (ABS) to release the hydraulic state.

[speculation] The dragging must occur with a duration longer than some specified time or distance. One quick tire chirp may not be enough to set the code.

Glad to see that your ABS is working! It had to be good for your brake system to move fluid through the spools.
Nowhere do I read the term "brake dragging" in the error description (you added it right?).

See, I would interpret that sentence to mean: "The rear wheel would not stop locking up even though the ABS ECU is telling the ABS solenoid to release fluid pressure". In other words, the "dragging" is being initiated by the rider's foot. ;)

But all of this is neither here, nor there, since David doesn't get the error code.

BTW, I had just recently done these tests, so I knew my ABS was healthy, but hadn't paid particular attention to how vigorously the lever rebounded on test #2. It's pretty darned vigorous.

 
I still don't get why you don't get a code 42. That would seem to describe this condition exactly (unless I'm reading it wrong).,
Code 42 = Brake dragging...
Nowhere do I read the term "brake dragging" in the error description (you added it right?).
Quoted directly out of my two part Gen I genuine paper Yamaha FSM, complete with black and white schematics in both volumes. In this thread I've tried to print direct quotes from the FSM in blue. It also says under Error 42 Check Point -- Rear wheel brake line.

Maybe I'll bring my manuals to brunch and we can compare... :lol:

I had hoped we had some oversight and missed something and the problem turned out to be anything other than the hydraulic control block. I really do hope that Yamaha can help David in some way. I'm sure the dealer will want to troubleshoot the problem for themselves. Plus, dealers get technical bulletins, supplemental technical manuals and updates us civilians don't, so they may have insight into the problem we don't.

I would like to mention that David has been excellent at working with the people trying to help him. Also, David has skills in following the FSM and being able to translate that into the work he has done on his bike. Too bad it looks like it's gonna have a ****** outcome.

 
Last edited by a moderator:
Maybe I'll try temperature changes like heat or dry ice while tapping on it and doing the tests...nothing to lose...unless it ISN'T the block and I manage to bugger it up.
I would be worried that I might dislodge some rust that would then be free in the system to foul other things up.

 
Last edited by a moderator:
Quoted directly out of my two part Gen I genuine paper Yamaha FSM, complete with black and white schematics in both volumes. In this thread I've tried to print direct quotes from the FSM in blue. It also says under Error 42 Check Point -- Rear wheel brake line.
Nevermind. I see that now. It's in the table on Pg 91 of the ABS supplement.

I was looking at Pg 96 where it runs down the troubleshooting steps for that code.

I think the "check points" are possible causes of the code. ie. things that you should check.

Still, that description does sound like what should register if a spool sticks open, even though that isn't listed as a "Check point". I believe the reason is, if you follow all of these troubleshooting steps all the way through to the end, the last thing they want you to do is replace the hydraulic control block.

 
Any update on this? :unsure:

Don
Not from me...I am waiting for the ECU that I bought on EBay to arrive. I'm almost positive that the ECU isn't the problem, but I figured for $59 shipped it was worth a shot anyway, and someone might need it at some point, if only to help diagnose a problem.

I PM'ed both OGAL and BumbleDB to ask if they resolved their similar issues but have not heard back from either. Last time I looked, neither had been on the forum lately. If anyone knows either of them, maybe ask them to post up if/how they solved their problems.

If, as I believe, the ECU isn't misbehaving, I'm going to the dealer to ask them to see if Yamaha will help out with the replacement of the pump. If Howie, Skooter, OGAL, BumbleDB and everyone else with the issue would do the same thing around the same time, pound the table about a safety issue, maybe Yamaha might be more willing to help. I've been scrounging the internetz for a salvage pump but haven't seen one at a decent price.

 
Last edited by a moderator:
Thanks for the heads up David :) If it were me and if Yamaha didn't seem willing to help I would be inclined to (temporarily) replace the brake fluid with something that might free-up/lubricate the solenoid spools. Only problem is I have no idea what to suggest. Obviously it would have to be something that was compatible with the seals :unsure: I have tried hunting around on the web but so far without success.

Don

 
Thanks for the heads up David :) If it were me and if Yamaha didn't seem willing to help I would be inclined to (temporarily) replace the brake fluid with something that might free-up/lubricate the solenoid spools. Only problem is I have no idea what to suggest. Obviously it would have to be something that was compatible with the seals :unsure: I have tried hunting around on the web but so far without success.

Don
I have been looking on the internet for reports of ABS failures that were not indicated by the warning light or by malfunction codes in 1st Gen models. So far I have seen 15 reports, including mine, that seem (as best I can determine) to have had a similar problem. Most of these are recent reports, within the last couple of years. A few indicated that replacing the hydraulic unit resolved the issue. No follow-up was reported for others.

daviddowns2000

SkooterG

RadioHowie

BumbleDB

OGAL

BlindSquirrel

TwoWhldTerror

SafeChris

Hycle

LetzRoll

Esteban

FJRRider RI (nestreetriders.com)

JCFarer (fixya.com)

JHL385 (https://www.fjrowners.com/phpbb2/viewtopic.php?t=6634&highlight=abs+failure)

Reaper (https://www.fjrowners.com/phpbb2/viewtopic.php?t=6634&highlight=abs+failure)

I doubt that this is a comprehensive list. It is also possible that I misinterpreted the problem for some, but it appears that this is not a really rare issue. You can also be sure that there are many more who just get it fixed and don't whine about it on the internet, not to mention those who have the problem and don't know it.

 
Last edited by a moderator:
To be fair, some of those on your list have yet to be diagnosed and/or repaired.

And I know for sure that Blind Squirrel said that his gave an ABS fault light and code, which was what the shop worked on.

For complete accuracy maybe you should separate the list into those key elements. You could even start a poll if you wanted.

ABS not working (Y/N)

ABS light indicated error (Y/N)

ABS codes stored (Y/N)

Root cause ECU, Hydraulic block, sensor, unknown (not fixed), etc.

 
To be fair, some of those on your list have yet to be diagnosed and/or repaired.

And I know for sure that Blind Squirrel said that his gave an ABS fault light and code, which was what the shop worked on.

For complete accuracy maybe you should separate the list into those key elements. You could even start a poll if you wanted.

ABS not working (Y/N)

ABS light indicated error (Y/N)

ABS codes stored (Y/N)

Root cause ECU, Hydraulic block, sensor, unknown (not fixed), etc.


Good idea, Fred. Hopefully some of those on the list will chime in with corrections or follow-ups. I guess there are a few reasons for ABS hydraulic unit failure and there may or may not be malfunction codes or indicator light signals. If frozen spool valves alone are the cause, it would be odd if some bikes would show a light or an error code and others would not.

 
Last edited by a moderator:
... If frozen spool valves alone are the cause, it would be odd if some bikes would show a light or an error code and others would not.
There are front/rear pressurization and depressurize actions. Not only does this involve the solenoids, there are large flow ports and small flow orifices. While the spool being frozen is high on the list of things to fail, it could also be a plugged orifice. Some of the fluid control actions may cause an error light and others may not.

We need to autopsy few dead 'uns to really understand the problem.

 
To all following this thread, I just ran across THIS in another thread, and for the $18 from RonAyers.com, I'm going to buy a new rear caliper piston and seal kit and rebuild my caliper.

Even if it doesn't correct my ABS dysfunction, it will probably go a LONG way towards ending my "rear pads evaporate in 5k miles" problem I've been having lately. Yep, they are noisy again and need to be shunted and replaced.

 
To all following this thread, I just ran across THIS in another thread, and for the $18 from RonAyers.com, I'm going to buy a new rear caliper piston and seal kit and rebuild my caliper.

Even if it doesn't correct my ABS dysfunction, it will probably go a LONG way towards ending my "rear pads evaporate in 5k miles" problem I've been having lately. Yep, they are noisy again and need to be shunted and replaced.
Very interesting. We need to consolidate these threads somehow. Mine fails test 2 (pedal does not return) and I've never had brake dragging AFAIK, so it isn't exactly the same, but I'll be interested in hearing how it works out for you.

 
Top