Sent wrong wire to ground. Now car will not turn on

I was trying to install a wiring harness for a trailer and I believe I sent a wire to ground that was not supposed to be grounded. When I tried to start the car I heard a few clicks and the lights flashed a little and my dashboard display read “malfunction”. Now my car will not turn on at all and if I leave the battery attached, all the lights flicker and the needles on the dashboard gauges wiggle back and forth. All wiring has since been put back the way it was and the fuses have been checked and all look good. The battery is outputting about 12.3 volts at most. But the car still will not turn on and all the lights and gauges flicker when the battery is attached.

Let’s hope you didn’t fry the BCM (body control module)

Why don’t people just buy the correct adapters?

And I do not know if that is the correct one for your car.


fuses look good? or tested good?

and your vehicle may have some fusible link wire- wire that is like a fuse and will blow when overloaded. These are usually right at the battery, and will be extra flimsy or burnt after “blowing.” Check for that.

After all applicable fuses and fusible links are verified good, suggest to charge battery to 100% with a battery charger & try again. 12.3 volts means the battery is very discharged. It should be 12.6 volts +. 12.3 volts may be confusing some of the computers. Especially on cranking the engine. You may also have to completely disconnect battery and let the car sit overnight before reconnecting battery, give an opportunity for all the computers to reset. Keep optimistic, hopefully this isn’t going to turn out to be serious electrical system damage.

Thanks all! So leaving the battery disconnected for a few days (mostly cuz I didn’t have a chance to do anything with it) and then jumping my car off another car seemed to do the trick! It did seem to reset the computer like u said and actually put my car back into “shipping mode.” One fuse that I guess is kind of more like a breaker needed to be pushed back in. I had a malfunction warning for my first drive around the block to charge up the battery but after resetting the warning light it never came back on again. Crisis averted, whew!

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