A4 aircon
 

Hi guys i have a 2012 a4 advant and my problem is. The clutch on the aircon pump is not connecting i have checked the voltage to find it is only getting 1.7v when i connect 12v it works fine. Please any ideas why the voltage so low. Ive checked fuses all seem ok except 1 by the ecu does not seem to be getting much volts please help