sounds sus to me, I'd be making sure the DSC error is the focus more to be fixed, cause I'm not sure what the shut off valve has to do with the fault.
Clean the leak and let it develop and monitor it, fix the actual DSC fault what ever the OBD2 code is.
I'd be thinking
ABS pump fault, or wheel speed sensor, but you need to know if the cruise control system is working and so on..best to get the code of the error if there is one. SCA can scan for codes for a small fee $14 or so.