If you are getting a reading of 12v and the cold start valve is not actuating, it's likely you are getting a "ghost voltage " reading. The volts are there but the power is not. Check with a loading meter or try and plug in a brake light bulb and see if it lights up.

If it doesn't light, check your grounds first.

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2