Disco 1 ABS LIGHT STAYING ON

My ABS light is staying on. Blink test gave out error code 3-6
"Hydraulic modulator solenoid valve, LH rear inlet - ECU connection/wiring"

Can anyone tell me how to fix this? MOT is on Wednesday!!!

It seems that you need to change the modulator, in that file with the fault codes(provided it's the one from autodata) is explained how to check resistance of the solenoid valves with multimeter so if you dont get around 7 Ohm between pins 21-27(fig 19) the solenoid within the modulator is gone or it's a wiring issue between the plug and modulator