2005 Gen 1 ABS bike. Brake question

I've always believed both my brakes activated the ABS system when used alone. Today I hit the rear a bit hard and the wheel locked up surprising me. 2 days ago, (900 miles ago) I had a new rear tire installed by a big dealer in Jackson MS, on Wed, and I guess I'm wondering if the ABS to the rear is not operating as intended. Shame on me for not practicing hard stops more often or I would better know the answer. On a road trip and will never see that dealer again.

It may be that the sensor for the rear isn't installed right or got damaged when the tire was changed. Take the right side case off and see if it's obvious.

I actually test my rear brake quite often. Until recently it gave both the characteristic "clunky" feel and sound of the ABS cycling and doing it's job.

A couple months ago I was shocked while performing this test. Much to my surprise the back wheel locked up causing me to skid about three feet. At first I actually didn't believe what just happened so I tried it again. Sure enough, another skid. So no more ABS functionality on my '05.

I never got the nerve to actually try locking up the front wheel in this manner.

If your sensor was correctly installed, perhaps your "ABS Block" is the culprit. The valves freeze up and no more ABS.

You can diagnose the ABS system.

The connector to engage the ABS tests is behind the RHS headlight/ dash panel





Photos from Bernie's post.

No need for the special Yamaha test lead

You just have to bridge out the Black/White and Sky Blue wires.

You can test the ABS ECU via the dash diagnostics and the ABS solenoid using the specific instruction, feeling the test in progress via the levers.

10:1 its the ABS solenoid, mainly due to a total lack of service.

The ABS solenoid needs to be flushed, just like the normal brake circuit and never ever gets done.

The procedure isn't in the manual, solenoids gum / seize up.

Other bikes with ABS do provide instructions.

Basically you flush with new fluid every year by engaging the ABS test while you bleed out the brakes.

Get new fluids in the solenoid and working the valves.

Eg, the Trophy test tool has a special test mode when performing the procedure.

Likewise for the Stelvio, a procedure in it's FSM

Give me a hoy if you want that info, should be on this forum

+1 to what Ray said about making sure that the sensor is not damaged and installed correctly after the tire change. Then the test procedure as per Ken. If there is no joy then you may be joining the multitude of GenI owners with a FUBARed rear ABS block. If it is the block, nobody has found a cure short of replacement. This seems to be one area where the GenII are more robust - haven't heard of many similar failures on the '06+ bikes.

I'd have thought it unlikely to be a sensor problem, ABS systems generally check the integrity of the sensors both stationary (measuring their resistance as you turn on the ignition) then checking that both are giving similar wheel speeds when moving.

Obvious check for that, put the bike on the centre-stand, run the engine and get the rear wheel speed up to (say) 20mph or so, expect the ABS warning light to come on, possibly with an error code of some sort (I don't know the exact behaviour of an '05 ABS).

Queensland Ken said:

You can diagnose the ABS system.No need for the special Yamaha test lead

Click to expand...

Awesome info, Ken - does it work for the Gen II also?

Welcome to the ''Gen 1 abs problem fan club''...Pretty common Gen 1 problem... A 04 and a 05 of my two friends have the same problem.The front brakes work fine.

But,from what they said they know why happened that.They didn't changed the brake fluid often but every 4-5 years and not every two years.

Also they didn't activated the system often,almost never activated it.Probably the old dirty fluid in combination to not activated the system often caused the valves to freeze up.The strange thing is why always happens in the rear brake in the most cases...

Mine still works fine,but i don't know for how long time yet...

eflyguy said:

Queensland Ken said:

You can diagnose the ABS system.No need for the special Yamaha test lead

Click to expand...

Awesome info, Ken - does it work for the Gen II also?

Click to expand...

Hi eflyguy,

Yep its the same procedure on all generations, all bar the 2015 / 16 where Yamaha removed the dash diagnostics.

Don't even know if the test coupler is installed on a Gen4 ??? or what Yamaha's test tool can do ???

I did write up a short version of the 2 procedures, it would be on one of my older hard drives somewhere.

The dash diagnostics is in the FSM but of course exercising, come bleeding out the ABS solenoid isn't.

If people want it, I'll find it or write up a new procedure.

It may very well be on this forum, try a Google search of the Forum

And I forgot to mention the most easiest test as mentioned by mcatrophy, spin up the rear then front wheel, only one wheel at a time to produce a ABS fault, or monitor the spinning wheel via a specific.diagnostic test .

And if a fault exists it can only be cleared via the ABS ECU diagnostics only.

Or I may have it on the Aussie Forum ???? Say around 2010 ??

FJRay said:

It may be that the sensor for the rear isn't installed right or got damaged when the tire was changed. Take the right side case off and see if it's obvious.

Click to expand...

Ray, the wheel looks normal so nothing obvious. Tried it several times today and the ABS is not working so I guess I will pull it apart in the next few days at home. Difficult to tell if the front ABS is working when loaded up so I after I get everything off I will test it.

Mihalis fjr said:

Welcome to the ''Gen 1 abs problem fan club''...Pretty common Gen 1 problem... A 04 and a 05 of my two friends have the same problem.The front brakes work fine.But,from what they said they know why happened that.They didn't changed the brake fluid often but every 4-5 years and not every two years.

Also they didn't activated the system often,almost never activated it.Probably the old dirty fluid in combination to not activated the system often caused the valves to freeze up.The strange thing is why always happens in the rear brake in the most cases...

Mine still works fine,but i don't know for how long time yet...

Click to expand...

Fresh fluid a few day earlier.

Fresh fluid? Any chance you overfilled the rear reservoir? I assume the brake released fully when you let up on the pedal?

Nothing will fix a seized hydraulic block, once buggered she is stuffed and costs a pretty penny.

ionbeam did a good write up on the test procedure, better than mine.

Just follow his instructions or you are just wasting your time.

Link to his post, Test and Maintain your ABS System

ABS ECU Diagnostics via the dash is in the FSM

I tend to agree that the ABS block is dun fer. I was just considering a couple of other possibilities worth investigating before condemnation of the block; especially since recent service (tire change and replacing brake hydraulic fluid) might have caused the problem. I suppose that the screwed up ABS may have predated the service work but hadn't been noticed.

Fully agree RossKean.

I worked on a mates ABS system, turned out the rear calliper piston was seized up with gunk.

It all tested out ok, but failed when riding the bike.

Something like the fluid pressure wasn't releasing. The worse thing is that the fault was very intermediate.

But it all boils down to a lack of maintenance.

I bet ya the dealers don't bleed out and work the solenoid valves.

Just out of curiosity, shouldn't people be reporting the ABS block failures to NHTSA? I would think the failure of a predominant safety feature, like ABS would result in a recall.

Edit - Guess I forgot where the jumper plug was. I followed the link to ionbeam's procedure, which is what I followed in the past and it mentions the jumper plug is under the battery cover.

Never tested my '14 yet, except in actual use, so this is a good reminder to get r dun during the spring preseason maintenance frenzy.

Queensland Ken said:

ionbeam did a good write up on the test procedure, better than mine.Just follow his instructions or you are just wasting your time.

Link to his post, Test and Maintain your ABS System

Click to expand...

Thanks, Ken.

Time to get back to my rear brake ABS issue. My damn service manual has no mention of ABS so I guess no help there. Someone mentioned that I should check the ABS fuse first to see if that failed. I did not know there was one and have no idea where to find it. Any comment on that?

I'm suspect of the local big dealer here in Tucson so looking for guidance to a smaller shop with a top notch Yamaha tech here or as far as Phoenix.

The ABS warning light does NOT come on under testing, front or rear. It does light up when turning the ignition on along with the various other dash lights.