I'm trying to help my friend fix her 01 neon thats been sitting for 2 years. I believe her mother jumped the car backwards, positive cable on negative and vice-versa. When I try to jump the car, it honks and the lights turn on and off in time with the honking. I disabled the alarm. When I try to start it, there's no start and the locks go open and closed rapidly and the guages dance around. Very strange.

So is the PCM fried? The fusebox looked fine, and I didn't find any burnt wiring anywhere.

 

oh man thats crazy...well the battery is probably done...

 

the battery as well as all of the electric control components are prolly FRIED! yes the PCM is prolly fried... but i would check and replace all fuses and relays before replacing the PCM

 

yea man that sucks.i almost got a saturn and it sat for 7 months and the battery was toast...good luck with that man

 

yeah check the battery, the terminals, and replace all the fuses first...my neon did some real whacky things when my terminals were toast..almost similar to this but it was still driveable and the locks didnt go crazy lol

 

The fuses seem fine. The battery is toast, I swapped in a good one and the locks and guages stopped going nuts. The PCM is giving the right DTCs to the codereader...so it might be okay. The starter however, is just making a humming noise and not starting.