Battery light comes on when truck is turned off

[travhous]

I have a 84 Mitsubishi 2.0l and when I shut the truck off the battery light comes on. There is also something slowly discharging the battery. I haven't had time to do any trouble shooting yet. Thought I would ask if anyone else has had this issue. Truck is all stock with no added accessories.

[geezer101]

Anything sketchy done to the electrics? The charge light shouldn't come on when you kill the ignition. A possible issue with the main relay? :shrug:

[pennyman1]

More than likely a shorted diode in the alternator - have it checked out.

[travhous]

It was the alternator. I had two spares laying around, of course the first one I tried did the same thing, but the second worked. What is disappointing the alternator that works isn't a oem Mitsubishi. This is for my all original '84. Well all original except tires and oil filter. Looks like I'm going to be looking for some who can hopefully repair one of the OEMs.

[geezer101]

Someone will be able to solder in some new diodes. The stock alternators are barely up to the job but I guess that's the compromise you have to make to keep it as near to original as possible.

[pennyman1]

or you can buy this OEM Mitsubishi alternator for $40.99 and its 75 amps: https://www.ebay.com/itm/BRAND-NEW-OEM-A2T03072-14445-ALTERNATOR-FITS-86-STARION-W-INTERCOOLER/273431036020?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

[geezer101]

...or what he said :P