[speed2th]

2010 BMW 335d with 77k miles. SES light came up, shown glow plug control unit cylinder 5 malfunction. Purchase a replacement and took it to a shop to install it. The SES light pop up right away with new code U0106 and P064C code. The mechanic double check connection and had no idea why. I search the code and indicated it is very likely a power issue or unlikely a defective unit although i cannot rule out. Does any one know how to fix this or does anyone know if there is a fuse controlling the power supply to the glow plug control unit? The car has been running rich with poor mpg and lot of carbon deposit at back bumper.

thanks