ABS fucked up MOT woes

[dubster]

Hi Gents,

1150gsa 2002 abs non-servo. MOT is on Friday so hope the collective knowledge here can help me out. 4 week waiting time at my local dealer and I'm supposed to be off to Romania on Saturday...

Got flashing ABS lights after key on. Had the day off so spent it cleaning calipers and flushing system. Noticed on rear caliper, one piston is working while the other will only extend once the other is held.

Have cleaned pistons, changed piston bore seals and applied silicon lube, but still the same as above.

Btw have reset abs also...

Is this a fucked caliper or any other suggestions?

 

[MattW]

Hi Gents,

1150gsa 2002 abs non-servo. MOT is on Friday so hope the collective knowledge here can help me out. 4 week waiting time at my local dealer and I'm supposed to be off to Romania on Saturday...

Got flashing ABS lights after key on. Had the day off so spent it cleaning calipers and flushing system. Noticed on rear caliper, one piston is working while the other will only extend once the other is held.

Have cleaned pistons, changed piston bore seals and applied silicon lube, but still the same as above.

Btw have reset abs also...

Is this a fucked caliper or any other suggestions?

Checked the sensor gaps?

Also check the sensor cables for any damage.

If its throwing an error on switch on then it'll be failing its initialisation self tests which points to towards some sort of abs component damage?

Thinking on my feet here - I'm sure others can offer other suggestions.

 

[jez]

I've no idea how to fix it but I stuck some black tape over the abs lights on my 1100 for the mot and got a pass no problem. I've no idea whether they bother with the abs for the test but better safe than sorry.

 

[dubster]

Hi thanks. sensor gaps checked ok. Must be summat else...

 

[MattW]

I've no idea how to fix it but I stuck some black tape over the abs lights on my 1100 for the mot and got a pass no problem. I've no idea whether they bother with the abs for the test but better safe than sorry.

What Jez sez.

Abs function doesn't form part of the test (my station turns it off for the brake tests) but I think that flashing lights on the dash are a fail (I stand to be corrected). So as long as your tester doesn't see the flashing lights you should be fine (tape or bulb removal).

 

[dubster]

.. and cables are fine. Spoken to my local MOT geezer and a piece of tape aint gonna cut the mustard

 

[dubster]

Cheers for that info guys. I guess i've been a donut and actually asked the tester about the issue. Seems like tape or removing lamps aint an aoption...

help please...

 

[dubster]

btw would rather fix it than bodge it

back to the caliper...

one piston will only move when the other is held.

Any ideas?

 

[MattW]

btw would rather fix it than bodge it

back to the caliper...

one piston will only move when the other is held.

Any ideas?

Slightly different friction in each piston. Not necessarily a problem as long as the brake works and doesn't drag.

This will also have nothing to do with the abs issue.

 

[dubster]

Thanks MattW. brake works fine. So one piston not working won't affect the abs self-test?

The alternating abs lights are starting right after key on (engine off). If i'm not wrong this shows a self-test fail. What could be causing the fail?

btw battery is showing 13v +

 

[MattW]

Thanks MattW. brake works fine. So one piston not working won't affect the abs self-test?

The alternating abs lights are starting right after key on (engine off). If i'm not wrong this shows a self-test fail. What could be causing the fail?

btw battery is showing 13v +

The abs power on self test doesn't (can't) test mechanical components like calipers, it looks for faults or communication issues with the electrical side of the abs system and sensors etc.

Have a look here - you can read the flash codes yourself:

http://www.largiader.com/abs/absfault.html

 

[Fanum]

Slightly different friction in each piston. Not necessarily a problem as long as the brake works and doesn't drag.

This will also have nothing to do with the abs issue.

Agreed.

Bulbs not working
Switches not working (stuck open or closed or not making any connection)
ABS pump itself
ABS sensors on wheels or the ring gear that triggers them
ECU
Wiring between any or all of the above.

I think that's all that would trigger a fault.....Pretty sure on an 11xx there are no pressure sensors working in a feedback loop, so in theory, you could cut the brake line and it wouldn't trigger the ABS lights until the pump was affected

How fast is the light flashing? (and which one)
If you ride the bike ten miles then turn it off and re-start it, does the light still flash?
Have you checked that the handguard isn't touching the hand brake, and that you can hear a tiny but distinct 'click' when you operate the two brake levers?
Have you reset the ABS ? (Take seat off, open diagnostic socket, bridge the middle connection to a good earth, turn on ignition, abs lights will be flashing alternately, hold ABS button for 10 seconds and the top light will go off and the lower one will stay on....release button, both lights should be on.Turn off ignition then restart bike as normal)

 

[Ian J Hartley]

I don't get it, as far as breaking efficiency goes, for the MOT on your bike, it makes no difference whether you have ABS or not.

The only physical evidence apart from lights and a switch that you have ABS or not is the sensors and sensor rings.

Bit of a ball breaker, but you could remove the sensors and sensor ring. Pull the fuse and unplug the relays. That way the lights won't come on.

There is a power relay located on the ABS module itself, which would need removing as well if you wanted to completely isolate the ABS, though I don't think you need to remove it for the MOT.

Then tell the tester you have had the ABS removed. Or take it to another testing station.

Ian

 

[Fanum]

I don't get it, as far as breaking efficiency goes, for the MOT on your bike, it makes no difference whether you have ABS or not.

Nope, but if you DO have it, it has to be working.
Same as a car spare tyre, and indeed ABS....don't have to have them, but if you do, they both have to be working and in a fit condition in the case of the tyre

 

[dubster]

Cheers. Firstly, good to know that the stuck piston isn't the cause of the ABS fault lights.

Problem is I've eliminated all the other possible faults (that I know of).

Honestly, I don't have time between now and friday to hash up the fault code LED system suggested at the end of the web page.

Anyone have any suggestions based on experience about what to do next?

 

[Steptoe]

Thanks MattW. brake works fine. So one piston not working won't affect the abs self-test?

The alternating abs lights are starting right after key on (engine off). If i'm not wrong this shows a self-test fail. What could be causing the fail?

btw battery is showing 13v +

As Matt has said, brake calipers etc do not effect the 1150 abs.

Agreed.

Bulbs not working
Switches not working (stuck open or closed or not making any connection)
ABS pump itself
Have you checked that the handguard isn't touching the hand brake, and that you can hear a tiny but distinct 'click' when you operate the two brake levers?

Bill, none of that is relevent on an non servo bike. The OP's bike is ABS only.

Have you reset the ABS ? (Take seat off, open diagnostic socket, bridge the middle connection to a good earth, turn on ignition, abs lights will be flashing alternately, hold ABS button for 10 seconds and the top light will go off and the lower one will stay on....release button, both lights should be on.Turn off ignition then restart bike as normal)

Bill, none of that information is of any use on an 1150. What you've posted is for an 1100. with a three pin diagnostic. Stop confusing the man..




To reset an 1150 with abs remove the cap on the round diagnostic plug and earth the brown wire, turn the ignition on and press the abs button for 8-10 seconds. then switch off ignition.


The abs isn't part of an mot test on a bike.

 

[Nobby]

To reset an 1150 with abs remove the cap on the round diagnostic plug and earth the brown wire, turn the ignition on and press the abs button for 8-10 seconds. then switch off ignition.




Come on waiting to see if it works

 

[Ian J Hartley]

Nope, but if you DO have it, it has to be working.

I Agree, and the best option is to get the ABS working, but failing that, the next best option must be to convince the tester that the bike has not got ABS fitted.

Either way it should pass the brake test.

Ian

 

[Colonel]

AFAIK abs is not part of MOT test for bikes (and I used to work in a test station) if brakes work ok (and they don't have to be good at all to pass an MOT) just take the bulb out and tell the tester it's been fixed - he will not know or probably even care....

I know this doesn't help with fixing the prob, which I guess is the main issue, but will get you a ticket to ride

 

[dubster]

Thank you Fanum and St Eptoe.

Bulbs ARE working.
front brake lever is free and unimpeded.

I will try again in the morn to sort this shit out.

Am I right then, based on your wise words, to believe that covering the lights with tape - the brakes do work! - will be enough for the MOT?

Cheers!