Low voltage from ECM to VVT.

[Jcb500]

Hi,
Very new to this site. What I got, 2005 s40 2.4i 5 speed, Moon roof. 170,000 miles. Original engine was over heated and burned out 3rd cylinder, car sat for 4 yrs. I got car and had a 60k mile engine put in. Car runs superb, but check engine light comes from a P0075 code. (poor signal from vvt)(intake variable valve timing solenoid). Volvo trained mechanic checked it out and says not enough electrical power coming from ECM to vvt. I sent ecm out to be fixed and was told there was a software issue, and ecm should now be proper.
The ecm is still throwing a P0075 code.

All suggestions are welcomed.

Joe in Albany, NY