Hi scotty, why is it that my overall electrical power/system in my subaru is losing or acting like crazy every time the temperature drops to 40 degrees and below? I already got new battery , new battery- harness and new alternator.
You either have a parasitic drain or your grounding connections are loose or corroded. Put a meter on your battery and check if your getting about 14.5 volts at idle. If not, your alternator, new or not, is not working correctly.
Thanks, Doc, I thought about that too. But why is the loss of electrical power only happen when the temp drops to 40? This evening when I drove home everything was ok again.
Metal - like the connectors in your wiring and grounds - contracts when it is cold. Add dust, rust, corrosion, etc. = bad connection when cold.
Read my last post again. It can only be one or more of the three things I pointed out.
After sitting overnight, check your battery voltage without the engine running. It should be about 12.75 volts. If not, you have a parasitic drain or the battery is faulty or the alternator is not charging properly. What do you mean by a new battery harness?
I replaced a new wiring/harness that connects from the alternator to the battery and to the starter. I will check if there's a parasitic draw. Thanks Doc.