Changed battery and alternator on a 2012 corolla s

Good evening,

So recently my corrola had died. And whilst trying to jump it my bud had his wires crossed and my horn went off. After trying to jump it several other times I came to the conclusion that either the alternator or batter had gone bad. So I replaced both. Now the car turns on fine. But electronics wont work. On the dash the abs, air sensor light, airbag, steering, skid,and brake lights are on. Car wint shift into drive. Ac doesnt work. Only hazards work, not individual blinkers. Is this a ECU problem? I have one ordered and on the way, I’m just hoping I didnt waste money

You may have fried the body control module.


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You ARE wasting money by replacing parts without proper diagnosis first. It would cost you far less money to have a pro diagnose and repair this.

I’m an e3 in the Navy, I learned once to start small and go from there. I got a code reader, and it wont even turn on

Luckily I have a one on the way, that’s what I figured all along but I’m not a car guy

You spent a good amount of money on a battery and an alternator without even putting a voltmeter on the old ones. To me, that doesn’t demonstrate good judgement.

Connecting the cables backwards usually causes fuses to blow. Check all of the fuses in the engine room fuse block. There is also a large grid fuse under a clear plastic cover, inspect for any blown segments.

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Completed that

Battery died twice before, wouldn’t start while jumped, or double wired to another car. Battery would hold the charge. Two faults that seem text book bad alternator for not being able to stay on after a jump, and bad battery for not being able to hold charge from a remote pack

I’m getting off this thread now, before I get charged with “bad behaviour”

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Thank you for the assistance and input. That was very enlightening and comprehensive way to help me figure out what’s wrong, as a forum would. If there was a rating system, I’d give you a 10

In addition to the fuses, did you find the heavy fuseable link?
And did you verify that they not only look OK, but have continuity?