battery went dead due to not driving it a lot.. went to jump it off and it backfired. so I stopped messing. took out battery and charged it, 12.6 .put battery back in and now no crank, no click from starter. checked voltage on purple wire at starter. 0 volts. I have triple checked all fuses. I think the security system has it disabled. I have tried the key relearn 4 times, no luck. I have two codes that are stored. what do these mean and what is some steps to diagnose..need car running to get it inspected..thanks
You could have a series of problems. First off, when you jumped the car, are you sure the polarity was correct? Reversed polarity will kill an ECU.
If your polarity was correct, the backfire you heard was because of the low voltage causing the car to be very rich. Old mechanic’s wisdom: Car backfires out of the carb, mixture is too lean. Car backfires out of the exhaust, mixture is too rich.
Next, charging you battery doesn’t guarantee its health. I just replaced one in one of my vehicles that was 12.97 volts and 0.25amps. I didn’t even know that was possible, but since cars run on their battery power with the alternator along to keep it charged, the battery depth is everything. Invest in a good battery tester, or take the battery to the auto parts store for an evaluation.
The lack of 12v power in your car could be internally corroded battery cables. This one stumped even a veteran mechanic friend for a couple days. The increased resistance in the cables makes the battery unable to spin the starter.
Lastly, the theft alarm system cuts power to the fuel pump, not the starter solenoid IIRC. Others may correct me if I’m wrong, so the fact that it’s not cranking is not necessarily due to the theft alarm system.
Check the battery health. Replace it if necessary. Replace the battery cables and clean the grounding points well. Reconnect the battery and connect your OBDII reader and try cranking it.
Let us know how you do.
