21/02/2026
2018 Subaru Forester, Engine # FB20YG###XX,VIN # JF1SK7KL5K######X and Engine Capacity 1998cc.The customer approached us regarding his vehicle whi h was experiencing electrical problems in the form of parasitic drain in its charging system (12 Volt battery).Every morning he will have to start up the engine with the help of a 12volt battery jumper pack because in the night before there would be a massive draw in the voltage causing the charging system to be not able to start the vehicle.A check engine light had also illuminated in the dash cluster set,once diagnosed a fault code P0137 (Oxygen Sensor circuit voltage low bank 1 sensor 2 was found,meaning the Oxygen sensor on the exhaust manifold was bad and needed changing.A brand new unit was bought and fitted,calibrated also.No.more check engine lights on that.The main parasitic drain diagnostics was done and 15+ DTCs were present for the AC (Air conditioner);B1430,B1434,B14A1,B14A2,B14E9,U0073,U0100,U0122,U0140,U0151,U0155,U0156,U0422,U0423 & U0457.A full electrical shorts check of both the engine bay fuse boxes were conducted,fuse box inside the cabin and the AC blower unit relays.Checks finally were done on the Climate Control Module,power was coming into it,but no power delivery was detected.It was conclusive that control module was indeed bad and was causing unnecessary draw from the 12volt battery.The unit was disconnected and customer was notified,and he has ordered a replacement unit,after which aircon gas can also be refilled after the necessary leak tests are done after the new module is fitted.There has since been no parasitic draw in the battery,vehicle starts normally every morning.Once the ac module arrives,than we will also patch up the leak in the washer reservoir.
Note : There is a caution sign in the dash for a faulty windshield washer system,which is from the leaking washer reservoir,once the leak is sealed up,the caution icon will disappear, that will be fixed too,once the replacement climate control module is replaced,with aircon gas filled as well,making the aircon system good again and functioning.