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2005 R12RT ABS failure in rain

roborider

God? What god?
I know someone had this problem, but I can't find it.

Yesterday, riding in the rain, I noticed an ABS warning (red triangle). The ABS whizzy pump was fine, and the brakes were great and still had power assist.

Starting up, the light would flash. Normally it will go out when you roll. But, instead, it gave an error. This makes me think it is a wheel sensor. Today, after sitting overnight, it is fine again. I'm going to check the wiring, sensors, connections, etc., but if someone has run into this, chime in!
 
Wow, error code from gs-911 was "Internal control module error-Frequency fault in control processor"

The fault was gone, and all tests passed. Both wheel sensors and wires are OK (as far as I traced the wires w/o removing tupperware). Both sensors read an identical speed. So, unless it comes back, I'll not worry about it.
 
I have heard of rear ABS system failures related specifically to the "wizzy" brake equipped bikes. If the ABS system has not been regularly exercized, or the fluid has never been flushed/replaced, I've heard of problems in the controller/pump unit.

I'd say monitor it, but if the fluid has not been flushed/replaced since the bike was new it'd be worth doing.
 
I do flush it every 1-2 years. Last time was October 2012 I think, but definitely in 2012.

I have heard about exercising the ABS, I'll go to some slick dirt or grass and do it. It is easy to do for the rear wheel, a little more "exciting" for the front wheel.
 
Have you checked the fluid levels in all the reservoirs? I know mine would do this as the rear pads wore down. I would get a flash here and there. Later it would check out fine. It was also a little temperature sensitive when at that threshold. Warmed up it was fine, when cold it would flash. I have also learned that this is the point that it is time to replace rear pads.

Good luck. Let us know what you find.
If you are like me you are looking for those nice spring days that typically start showing in late in February. I am a bit tired of the cold this winter.

Oh.. what color is your RT?

NCS
 
I've checked the level in the primary reservoirs (at the handlebar, under the seat), but to check the ABS circuit you have to remove the tank and for that, I need to see the failure recur. Right now, I'm researching the error. Pads are less than 50% worn, but I have a set on the shelf waiting to go probably end of this year or next (I brake HARD).

Yeah, I'm ready for spring. I went riding Sunday which was 39 F and raining, but hey, it was a riding day. I ride year round. NC twisties were good 3 weeks ago but I see they got more snow again.

Bike color. Well, depends on when.

I bought it new as a charcoal colored "black" bike.

After a lowside in the sand on the NC Twisties, I repainted it in my shop to red.

After some "incidents" with police, I decided red was not for me, and I repainted it blue. I wanted a darker blue, but this blue seemed darker at the paint supply store than it turned out. So, who knows what color next year!

Original:
IMG_5771_zps86359faa.jpg

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Post low side:
CopyofIMG_6635.jpg

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Current: (except I swapped the red tape on side and wheels to matching blue)
photo_zpsf69f67b5.jpg
 
Hopefully it will be something simple. Perhaps a sensor or even the level you haven't checked.

My pads on the rear wear fast as well 15-18K and they hardly ever get touched by themselves, using front mostly which is linked to the rear.

I asked about the color as I had a blue RT come off 540 maybe a week ago onto 40 west late afternoon as I passed that ramp. Yes yours is blue but I was running 75-80 and it sounds like you would have joined. This person didn't but stayed in the slower lanes at about 70-73.

Again, Hope you find a simple reason for the fault.

NCS
 
My bike with "Whizzy" brakes did the same thing when I bought it a little over 6 years. The owner warned me before I bought it. He said it started after the rear caliper hung from the wires when his brother was doing something to the bike. It did it once when washed the bike and used high pressure. After it did it with me, I put some sealer where the wires met metal and it has not done it in the 5+ years since. I suspect you might have a bare spot in the wire going to the sensor.
 
I could not find a bare spot but that doesn't mean it is not there. I will ride it again and if it is a 'wet only' failure, I will look harder. I'll also try the hose on one wheel at a time. If a sensor is bad, the GS 911 should find it. I'll post more if I learn more.

There is a lot of info on ABS problems, including some great posts by Don, our moderator, but not much for this specific error. I found one post with this exact error on a Google forum, but it was never resolved.
 
Like the paint but I suspect that blue tape won't do much for protection...

Only whizzies I've got are on my 06 K-GT (my RT is an 08) but I'll be interested to hear if you ever nail down the cause of this odd behavior..
 
I didn't install the red, or blue, tape for protection, just liked the looks. But, it is the 3M reflective tape, and both the red and blue (or any color), light up like fire at night when a headlight hits it. I don't get to see it as the rider, but I've been told by my buddies that it shines brightly. I think I have a pic somewhere....I promise if I learn anything on this I will report back.
 
Took the bike out today, all was normal. ABS worked on the rear brake (did not try the front). I will ride a lot this weekend. If all looks good, I will try the hose and see if I can create a failure.
 
Do you know if the '05 recall on the front sensor was addressed on your bike?

I recall it was a reroute of the front sensor wire as it was too close to the rotor. Mine had a wear spot on jacket,caught in time and replaced.
 
Yes, it was, very early on. The wire was never close to the disc, but it was rerouted or clipped or whatever they did. The wires look great. My front wheel sensor is a bit smushed, I must have hit it when removing a wheel, but it is not cracked. Well, it does not APPEAR to be cracked.
 
I got it figured out.
Pretty much everyone was on the right track. The error came back on another rain ride.
On closer inspection, removing the sensor, I found it did have a crack. I pried it a bit with a knife blade and the piece came out. I patched it with some marine epoxy and it is fine now. If I need a new one, it is $122! So hopefully this fixes it.
The GS911 helped locate the problem. When I rotated the front wheel, the speed showed 0 mph when the sensor was wet, worked properly when the sensor was dry. Also, you can see, if you slowly rotate a wheel, the sensor voltage change from about 0.5 volts to 1.5 volts. When the magnetic sensor is near the metal part of the ABS ring, the voltage rises. You also can place a screwdriver on the sensor and the voltage will rise. This sensor, when wet, always read 0.5 volts.

Picture of the sensor:
wheelsensor_zpsa47d20e5.jpg

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Screen shot from GS911 showing voltages and speed readouts of the wheels near the mouse cursor:
GS911_zps5eb33162.jpg
 
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