Disco 2 ABS Modulator bleeping noise

Got time on my hands so posting this to pass some of it!
My D2 ABS modulator block makes a very faint bleeping electronic noise which you can hear when working under the bonnet.
What is this and is it normal?
Im curious as my battery seems to have a bit of a drain on it. Nothing mega but wondered if this could a culprit. Its probably just me not using it for any decent journeys lately!
Cheers

no should only operate when brakes are and then only when abs or function is triggered

ronsealdeath said:

Got time on my hands so posting this to pass some of it!
My D2 ABS modulator block makes a very faint bleeping electronic noise which you can hear when working under the bonnet.
What is this and is it normal?
Im curious as my battery seems to have a bit of a drain on it. Nothing mega but wondered if this could a culprit. Its probably just me not using it for any decent journeys lately!
Cheers

Click to expand...

Mine does it, and can be left for weeks without draining the battery..

Interesting thanks both. So it isn’t normal, but isn't an issue.
Thanks again

ronsealdeath said:

Got time on my hands so posting this to pass some of it!
My D2 ABS modulator block makes a very faint bleeping electronic noise which you can hear when working under the bonnet.
What is this and is it normal?
Im curious as my battery seems to have a bit of a drain on it. Nothing mega but wondered if this could a culprit. Its probably just me not using it for any decent journeys lately!
Cheers

Click to expand...

IMO it's not normal but happens a lot, not all of them are doing it but quite many, it's a SLABS ECU constructional misbehaviour, the gist is that any door open signal powers up the SLABS ECU for the SLS to relevel if load is removed from the vehicle and being under power there is some low voltage parasitic induction into the modulator's circuit too which makes the internal valves to click randomly... nothing bad happens just that it can be annoying... mine is rarely doing that, actually not at all lately, it's something to live with without fear

the parasitic drain of the SLABS is around 0.5A and it's only for 1.5 hour after the ignition was off or for 30 minutes after a door was opened then the ECU goes to sleep so if a strong battery goes flat over night or in a couple of days better investigate further cos there's some other reason

Thanks SF thats really interesting. I do get some misbehaviour from my SLABS systems like the SLS pump going for a second after ignition switched off, levelling itself at junctions on hills and HDC showing some odd behaviour when being used (chime randomly sounding).
It all works fine but i just wonder if as they are getting old, these ECUs are doing odd things.
Thanks again

Henry_b said:

Mine does it, and can be left for weeks without draining the battery..

Click to expand...

I have the same experience.