ABS issue

Hello all,
As it was necessary, my beautiful Bordeaux eventually make whims ...
So here's the scene:
This morning, on the road work, the ABS warning light fix. It had never flashed or another before, and my last purge ABS / Diag is less than two months.
So on returning at home, I plug the tool that goes well, and there, in amazement, the bike does not fit in diag mode, And staying the hands / feet on the brakes, not ABS purge ... WTF ... However, I have a signal on pin T / B of the shunt.
Unfortunately, here the limits of my little voltmeter, it is not fast enough to read the error code, so it's impossible to count how sour the long / short pulse.
I see three long but short ???
So Have you an idee why the diag mode doesn't start? Have you already heard about this probleme?

Thanks for all your idees

Umm..lost in translation. I am trying to understand what your problem is. Is the ABS light coming on and you don't know why or does the ABS not seem to be working?

If the ABS warning light is on, it is almost always related to the front/rear wheel sensor or the wiring to the sensor.

Trying to see the ABS error codes is one of the few times that a very inexpensive needle movement analog miltimeter works best.

The method to access the diagnostic screens is described in this thread: https://www.fjrforum.com/forum/index.php?showtopic=9612

sorry.
Yes, the light is comming during my commut.
I used the yamaha shunt (90890-03149) to try to have ABS error on my screen, but the system doesn't start the in ABS diag mode.
I try to make the purge, but nothing happens.

With a voltmetre, check the signal on T/B output of the shunt, and they are a signal. My voltmetre is to slow to read it. I will try again this evning with on osciloscope.

ionbeam said:

If the ABS warning light is on, it is almost always related to the front/rear wheel sensor or the wiring to the sensor.
Trying to see the ABS error codes is one of the few times that a very inexpensive needle movement analog miltimeter works best.

Click to expand...

yes, yesterday I had only a low cost numerique voltmetre. I hope with the osciloscope, it will be better.

TomInPA said:

The method to access the diagnostic screens is described in this thread: https://www.fjrforum.com/forum/index.php?showtopic=9612

Click to expand...

Thanks, I do that yesterday, and they are no error log on the ECU. So my only hope is with the osciloscope.

TomInPA said:

The method to access the diagnostic screens is described in this thread: https://www.fjrforum.com/forum/index.php?showtopic=9612

Click to expand...

Remember you need the jumper / come test lead to access the ABS diagnostics.

It's not a ECU function.

A good link

yes, I do first the ECU diad, (without the jumper) and after, I turn off my FJR, plug the jumper/shunt (I don't know the correct translation) to inter in the ABS diagnostics.

Unfortunatly, ABS diagnostics doesn't start.

Bummer,

Did you use the Yamaha lead or a jumper wire / alligator clips and definitely bridged out the Black/White and Sky Blue wires within the 4 wire terminal block ?

If the ABS ECU doesn't go into diagnostic mode, it would tend to suggest that it's crook.

I've had 2 mates who have been touring with ABS problems, one had a loose transducer after having a tyre changed and the other had crud debris built up within the magnets.

Check all the connectors and open / re-seat them a few times each.

Yes, I use the Yamaha connector.

I Will check again all connectors.

So according to the osciloscope, I have the code 16 and 25.

https://i35.servimg.com/u/f35/17/50/36/72/dsc_0810.jpg

gapiob said:

So according to the osciloscope, I have the code 16 and 25.https://i35.servimg.com/u/f35/17/50/36/72/dsc_0810.jpg

Click to expand...

As previously mentioned, it is usually the wheel sensors that cause a solid ON ABS warning light.

Code 16 indicates that there is no continuity in a wheel sensor -- the sensor is electrically open. Either the sensor is bad, the connector pins are corroded or there is a broken wire.

Code 25 indicates that there is no signal from the front wheel sensor when the motorcycle starts to move.

Indeed, I have check this two point... And they are all ok

At the connector of the abs calculator, I have 1.3 kohms, for front and rear senior.

I have checked all connectors, and they are all ok.

Next step I Will check with an another abs calculator.

Thanks for all your idee.

Yesterday, I tried a new ABS ECU, and a new ABS spider... With the same result. sad, but not surprising.

As several of you have said, I return to rear wheel sensor, So, new ABS sensor and ABS flange are ordered. As you can see, mine is split on almost all round.

So I'll changed all. wait and see.

Well, just for you, a little summary.

So, brutally, the ABS warning FJR stay on, more I had more speed information / reliable distances traveled.

Putting the ABS jumper did not change anything, I can not enter the diag mode ABS, and the main diag mode gave me no errors.

It's also impossible to trigger the bleed ABS.

Sacred list of symptoms ... and good time with this...

Namely, the ABS ECU has a digital output that generates error codes while he is alive. This is the pin T/B of the ABS jumper. Do not try to read this signal with a digital multimeter, they are too slow ... To read the signal, 3 ways.

- You have the analog meter, and you watch the needle move

- A simple bulb (watch your fingers holding it)

- An oscilloscope (I have it at work)

So here's the signal to oscilo.



2 error codes are observed:

- The first is 1 long and 6 short, so 16

- The second is 2 long and 5 short, so 25.

Anyway after reading the doc ABS, rear sensor feels his ....

I check this one has the ohmmeter across the ABS ECU, and this value is perfect, sh@t that was too easy ...

With Ced (an friend who had some part of FJR) we test the ABS ECU, and no changes ... well that's not it ...

After a good night's slumber, and 1 or 2, or I know how much more glass of aid to reflection, from the Caribbean ... (accompanying a BBQ ), an idea every beast me just ... (And yes everything is possible).

- The sensor has 2 pins connected to the ECU, so this is a impedance "floating" with respect to the mass of the bike. Otherwise one back to the ABS ECU enough ... So before starting my day, small check on the bike... That's it. One of the two spindle was a mass of the bike ... just by removing the flange of the rear wheel (but leaving the connected sensor), more mistakes. So via the flange, the ABS sensor was on the mass.

Replacing all rear flange sensor has solved the problem.

In short, the final two days after a ride with, all is well, thanks to all those who help me eliminate bad assumptions, and thank you to Frank (https://www.gn-moto.com) for parts .

My translation of your problem is that there was an electrical short circuit between one of the sensor wires and the frame?

If so, that's unusual, but an easy fix once you know what it is.

New check for anyone with ABS issues: check for a short between the sensor wires and the metalwork.

Indeed, It's that, And like it's very unusual, I lost time to check this point.
I tried to describe all the symptoms to help the next rider who would this problem to fix it quickly.

Glad you were able to find and correct the problem. Thanks for taking the time to post the details.

There have been some who have had aluminum corrosion in the sensor housing (wheel flange) which has caused ABS issues and/or difficulty to remove the sensor. Is this where the "short" was? Otherwise all I can think of is a damaged wire......... in any event, it is always advisable to remove the sensors during wheel/tire changes, to check for this corrosion and to prevent damage to the sensor wires. I've seen a few who do not remove their sensors and leave them in the wheel flange dangling while they do a tire change..... not a good practice IMHO.