forester2002s Posted January 10, 2018 Share Posted January 10, 2018 Could be faulty diodes in the alternator. Do a search on this forum. There should be plenty of posts about failed diodes. Quote Link to comment Share on other sites More sharing options...
fgf Posted January 12, 2018 Share Posted January 12, 2018 Some test info: '96 Legacy, EJ22 engine, key off & removed mA meter between -battery post and post clamp. 65 mA steady current after 1 minute (to let ECU settle down) = 1.5 Ah/day = 47 Ah/month Group 35 batteries used in the '96 typically list ~ 40 Ah capacity, so could discharge battery in a month... Leaving my UltraGauge (OBDII viewer) plugged in doubled the draw - apparently it keeps checking to see if the key has been turned on yet - so only 2 weeks to discharge battery. Got bitten when I didn't start the car for several weeks followed by a sub-zero cold snap (discharged batteries freeze easily)... Quote Link to comment Share on other sites More sharing options...
Boxer Medic Posted January 13, 2018 Share Posted January 13, 2018 (edited) This might help out some. It has helped me learn by watching it be done methodically and competently. Edited January 13, 2018 by Boxer Medic Quote Link to comment Share on other sites More sharing options...
Bushwick Posted February 11, 2018 Author Share Posted February 11, 2018 (edited) Wanted to update to possibly save someone else the headache in the future. You definitely NEED BOTH wires going to the alt (constant 12v+ AND the "dummy light" wire ). 12v+ constant *can* be attached to the right-side (if looking down at engine from front of car orientation) terminal and will allow alt to charge but needs a key-on activated relay to avoid draining battery at engine off. After getting both wires in proper orientation and connected, no drain and car can sit w/o being dead overnight. My mistake for thinking they could be run as a 1-wire set up as-is. Connector plug was cut to get the Tribecca alt to work before, and once reverting back to the factory-style alt, saw it was charging with right-side getting fed 12v+ constant and assumed it was correct. Since the drain can take days to leave battery dead to months in warmer weather, and alt was testing OK with good diodes; like chasing a group of wild turkeys. Edited February 11, 2018 by Bushwick 1 Quote Link to comment Share on other sites More sharing options...
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