Hi. I need help from owners of ML 270 CDI. My MAF is not functioning. Connected or disconnected engine runs the same. Either it is dead or not powered. MAF connector has 4 wires . Red/Blue wire from socket #2 runs all the way to ECU and supposedly should deliver 12 volt to MAF when measured between sockets 2 and 3(grown). I have no voltage. If somebody can help me sort it out by disconnecting MAF and measuring voltage between socket 2 and 3 with key in position 2 . If there is voltage then possibly my ECU at fault... Appreciate help.