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2002 R1150RT brake failure

I think the self test on that unit calls for 13.8 volts!!!

When in failure mode the brake light comes on when the front brake is applied. I haven't changed the bulb but did clean the contact of the bulb and checked for corrosion in the socket. I will replace bulb.

The battery checks at 12.80 volts with key off drops to lower 12s when key is on lower 13s running. there is no drop of amperage when in the fail mode.

Will try the master reset. I will assume the bike needs to be running? does it need to be in the fail mode or can this be done any time?

Thanks for the reply.

Rick

I understand a lot of ABS units from this era would go into default because of low battery voltage. I might give some thought to putting in a newer and better battery (Oddessy) before getting carried away to far on other things. 12.80 volts key on and low 13's tells me it might be a low battery voltage thing. The ABS computers on these bikes are pretty tough so I would be surprised if its that. Oh and visually check your front brake switch on the M/C and make sure you don't have a leaky M/C that's messing up the switch, then check bulbs. I would put my money on a weak battery.
 
Now that is good advice.

I understand a lot of ABS units from this era would go into default because of low battery voltage. I might give some thought to putting in a newer and better battery (Oddessy) before getting carried away to far on other things. 12.80 volts key on and low 13's tells me it might be a low battery voltage thing. The ABS computers on these bikes are pretty tough so I would be surprised if its that. Oh and visually check your front brake switch on the M/C and make sure you don't have a leaky M/C that's messing up the switch, then check bulbs. I would put my money on a weak battery.

If someone could tell you how to pull a code, it might confirm the low voltage thing that everybody complains about.

I don't like buying batteries when I'm not sure that is the problem and I can't comment on the Oddessy. I am certainly not going to buy the battery that Roger04rt has been complaining about for the last three months.

After the comment about low battery voltage, try starting the bike with a booster pack or jumpers from another vehicle? Is that even a reasonable way to try to troubleshoot?

I installed a chunk of welding cable on my battery for boosting if I need but I rather doubt most people have chunks of welding cable and lugs lying around their garage.
 
start it, put in gear, ride off, accelerate to 4K RPM, leave in gear, leave the clutch alone. key switch off, wait a second, switch on. You have reset the abs. I will initialize just fine. I have done this. Battery out of equation. I have a bent sensor wheel from careless tire change, it cleared the fault, for a while.
It is a fact that all the brake hoses they used in that era are defective, with age the inner liner will break up and little chunks of rubber will appear. You can ignore it, hope non of them get in anything important, or you can replace them with Teflon lines ones. wait too long and the expense of the repair just rises.

so this needs done no matter what, and if the good bleed fixes the problem then you are lucky. If not then pulling codes is next.

Rod.
 
The first thing I did was buy a new battery not a oddessy but a sealed battery. I have also cleared the`failure flasher and connected a battery charger to battery I can pull the front brake or push rear brake pedal maybe 30 times and each time the servo fires up then failure light will come on.When that happens the front brake lever will not activate the servo and the rear will activate the servo but it sticks on continuing to run even when the brake pedal is released.

I wish I had a code reader I think (if I read this right) the code reader GS911 could read the ABS problem.Trouble is they cost hundreds of $. My limited use of a reader would negate buying one.

My air head could use a new battery if you think a Oddessy would help I could get one for the 1150 and pass the one I bought for 1150 to the air head . It is the battery I wanted to begin with but local store had to order and I didnt have the patents to wait.

I clean the wheel sensor but the bike will go into failure mode while setting as described above.

I may have to bite the bullet and haul it to shop to have code read. Wanted to maybe get lucky and fix this gremlin before that.

Could the ABS relay switch have anything to do with this?

Again thanks to all.

R
 
Hi Rick,
I just removed and reinstalled my ABS unit while replacing my alternator's regulator so that it properly charges the odyssey pc680 battery. I don't think you need to change out the new battery you bought. It sounds like you have a real problem in the ABS unit. Out of curiosity, which battery did you buy?

I don't know the ABS unit very well, but I just used my GS-911 to read ABS codes and to perform a full pressure bleed-down test that the GS-911 supports. I will take a screen shot of the status data which will give you an idea what's going on.

The computer is looking at wheel spin from the wheel sensors, monitoring internal hydraulic pressure with sensors it has and watching for the brake switch to OPEN. On some bikes the brake's switches close when you apply them, on the R1150RT, the contacts open when you apply the brakes.

If the wheel rotation sensor or connector has a problem, it will fault. I'm told that any brake fluid spilled into those little connectors will damage them. They are the small ones on the top of the ABS. Carefully remove each connector and look inside.

If the brake switch or wiring has an intermittent open, that may cause a fault. Doug Raymond who made these (http://www.mac-pac.org/wp-content/uploads/2011/01/R1150RT-Electric-Diagram-V3.1.pdf) great schematics told me just recently that it took him a long time to find an intermittent switch.

What color was the fluid when you bled the brakes, and how particle filled was it? Look the rubber lines over from end to end, others have seen bulges. If the line bulges under pressure as the fluid warms, that could trigger a fault.

I would certainly look into borrowing a GS-911, I'd loan you mine if I were closer but I use it quite often.

I'll get a screen shot of the ABS status and add it in a few minutes.
RB
 
Hi Rick,
Look the rubber lines over from end to end, others have seen bulges. If the line bulges under pressure as the fluid warms, that could trigger a fault.

RB

those lines can rupture internally, and may give no outward sign of failure whatsoever. that's what happened with my buddies. eventually, they began leaking, but he'd already had the shop replace the ABS pump, to no direct benefit.
those lines were "adequate" when new, and only deteriorate and degrade with age.

Just replace them. They're not real costly (full set is maybe $200), doing so will improve brake feel and performance, and they are pretty much a lifetime upgrade. Might even solve the OP's brake issue.
 
those lines can rupture internally, and may give no outward sign of failure whatsoever. that's what happened with my buddies. eventually, they began leaking, but he'd already had the shop replace the ABS pump, to no direct benefit.
those lines were "adequate" when new, and only deteriorate and degrade with age.

Just replace them. They're not real costly (full set is maybe $200), doing so will improve brake feel and performance, and they are pretty much a lifetime upgrade. Might even solve the OP's brake issue.

BF, I have the same issue myself. After pulling the pump and reinstalling/bleeding the brakes are much more solid but I have the original rubber lines. My tank lines, I know they're differnt, were a mess. If many others have had brake line failures I can't see why mine would be different. The fluid was quite dark when changed it this weekend.
 
Thanks Roger and Bikerfish for your comments.
The rubber lines MUST be replaced before proceeding to troubleshoot other issues.
Safety first, failures can happen even when the machine is off
One client of mine was almost crushed unloading his bike off a pickup truck when the front master line bulged and the lever went to the handgrip.
 
Here is the GS-911 status report, if you had a GS-911 you might be able to directly see what it was objecting too:

absstatus.jpg


And here is a realtime values report from the other sensors for your reference

motronic2.4status.jpg
 
Thanks Roger and Bikerfish for your comments.
The rubber lines MUST be replaced before proceeding to troubleshoot other issues.
Safety first, failures can happen even when the machine is off
One client of mine was almost crushed unloading his bike off a pickup truck when the front master line bulged and the lever went to the handgrip.


I picked up a pirate GS for a buddy to repair and flip( he thought he found a deal)...luckily I was loading/walking into the trailer when I tapped the front brake with a squishy feel then nothing as it slammed into the wheel chock on a downhill slope. It had felt fine prior to rolling down the hill.

When I took a look under the beak, the bulging line was evident and had a beer can and hose clamps around the bulge:banghead What was the PO thinking?

Also many issues as mentioned on other bikes due to decayed lines that looked OK on the outside. I recently repaired a 2005 LT with a blown front splitter line.
You may not THINK you have issues with older lines, however, they are an issue that will cause most some problems. Cheap upgrade in the bigger scheme of "what if" . All current models come standard with SS lines I believe.

AndyVH had a good thread on this last year with some good info, I couldn't locate it but hopefully he may chime in. He has extensive knowledge on rubber lines.

And on a moderator note...please keep this civil fellas...it's too early in the season to start this tit-for-tat It's OK to have opinions...just try respecting each other...MOD hat off>
 
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Thanks

Thanks for all the help.
.:banghead

I think at this time my best bet would be to just take it to the shop and have them code the thing and hopefully pinpoint the problem. I have done the simple cheap things and no magic bullet.

If it turns out to be the servo unit I have some time to replace, repair or remove the unit.

Thanks to All !

Rick
 
Rear brake switch?

Have you checked the rear brake switch?
Crud in there could prevent switch closure and account for the sticking ABS pump.
It's very easy to inspect and clean.
 
For anyone interested, Rick's 1150RT was showing a front motor fault. So after a good brake flush he worked up the courage to engage the ABS. First the foot pedal and then the hand lever. From the way it was acting I suspected an electrical fault such as carbon or corrosion on the ABS motor armature. So far so good but since the wind chill here is below zero with highs below freezing for the coming week, it'll be awhile before we know for certain.
 
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