Brake warning stays lit after ABS activation

On my 2010 GSA the brake warning light goes off when I ride off as per normal, but I've noticed that if I trigger the rear ABS (e.g. on a bit of bad surface whilst braking for a roundabout) the "brake warning" and ASC lights stay illuminated.

After switching the ignition off and then on again the ASC & brake warning lights go off when I ride off and then stay off (unless I trigger the ABS again). I'd expect the brake warning/ASC lights to not stay on after triggering the ABS - any ideas?

The speedo is working fine by the way so I'm assuming it's not a dodgy speed sensor. This is what the dash looks like after triggering the ABS:

check for posts where the ABS module is dead (they all do it, and yours is the age to die BMW built it with)

its likely the brushes in the abs pump are dirty its a DIY if you are BRAVE.... I would NOT recco you go to a BMW dealer to get fixed. they'll take £1800 for a job that can be done for free, and in another 7 years it'll need another pump

I've a suspicion that that's what the system is meant to do. If I trigger my ASC by crossing a patch of wet grass and being heavy-handed on the throttle I get the ASC warning light until I turn the ignition off. I could believe that the lights stay on to let the rider know what's happened.

Bear said:

I've a suspicion that that's what the system is meant to do. If I trigger my ASC by crossing a patch of wet grass and being heavy-handed on the throttle I get the ASC warning light until I turn the ignition off. I could believe that the lights stay on to let the rider know what's happened.

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that sounds like a different fault (probably an abs sensor dying), if the traction control (TC / ASR / ASC etc. its all much the same thing) activates, it flashes the light while assisting to indicate that you should be driving bit more smoothly as the current conditions are difficult….

If after its helped, the light remains lit, its indicating a fault (I tried to help, went wrong, threw the warning light) so you know you can't rely on its function / supporting as it usually does.

A key on / off cycle runs the self test again, if the result comes back ok, it may think its OK, if it detects slip TC goes wrong again and throws the light again. I suggest you understand how to disable or you may not be able to ride it home when it dies completely

OK so my 2010 has 49k on it so I might be in the "ABS unit failure" zone but yesterday whilst riding along not using the brakes the warning lights came up again (as per post #1 above). First time it's ever come up without using the brakes.
Toggling the ignition cleared the lights and when I got home I plugged in Motoscan and I'm showing 3 errors, none of which I think relate to the ABS unit itself?


In the past when the speed sensor has checked out I've also lost the speedo - fitting a new sensor has resolved the problem. The speedo is still working so at the moment so I'm thinking:
1) It's not a problem with the ABS unit
2) I might need a new speed sensor soon

rear sensor wires breaking is normal on a BMW

dealer diagnostics reporting the wrong end at fault is also normal...

now you have the codes delete them, no value to anyone, then go for a ride and see which come back.. the trouble with stored codes is you don't know which ones are still real

at 49k I can belive both the ABS is dead due to age and the rear sensor wires worn out due to mileage.... the skill is in developing enough failures that way most don't know they are being taken for a ride