2016 Subaru Outback dead battery
2016 Subaru Outback. 3 years and 3 batteries. Something is wrong. The car
will jumper off from another vehicle and run just fine but overnight the battery
goes dead. I'm thinking alternator but may be something else electrical or
computer related.
This is a common issue. Are you using the low capacity Subaru batteries? If so get a high capacity battery like Odyssey or Optima which will reduce or eliminate the issue. Has Subaru done a battery draw test?
2017 legacy, same deal. There is a 7.5A fuse for the DCM I checked it myself and have proof that this is drawing excessive amperage from the car parked without the key in the ignition.
Their "Battery Management System" starves the battery to death ! First, it will not immediately charge back the energy that it used to start the car; then it "decides" to not maintain nationally recognized Terminal Voltages for Lead-Acid Batteries: The First thing the car should do is to FULLY Re-Charge the Battery; when this is not done immediately, the battery begins a slow march to High Sulphation of the Battery Plates ; this reversible process requires special equip, beyond the car's capability : That is why it must be #1 Priority after starting ! The Second thing the Car should do is to Maintain 13.2-Volts ABSOLUTE MINIMUM at all times while the vehicle is running, with a Max. Voltage of ~14.75 : SUBARU NEVER ATTAINS THIS REQUIREMENT .... EVER !!!!!! In FACT they intentionally cycle the Alternator System OFF for extended periods of time, in the ILLUSION that they are doing REGENERATIVE ENERGY OPERATIONS ... using a Lead-Acid Battery !!! What Regen Features that might be possible, can only be achieved SAFELY with a Deep-Cycle Battery - which are poorly suited for STARTER Batteries !!! The only exception being a Very Expensive Lithium-Ion Type of Battery !!!!! I doubt that Subaru will ever acknowledge this Automotive HERESY !!!!
