ABS fault 164?

[highwayman306]

Hi guys

need a little assistance. I had the abs and handbrake light come on 4 days before mot...now its failed.

Ive had the fault read and it has come back as '164 rear left valve'

Can someone confirm what this is please, its rather urgent as i need the car for work

I seem to think that this might be the pump itself...not the n/s rear abs sensor???
I just don't know

Thanks in advance

[highwayman306]

so looks like its the pump then, thanks to toseland and tom (tup)

so things i need for this job...just to get it through the MOT...:

Pump
2l brake fluid
maybe recon'd rear calipers

FML