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2002 Saturn SL2 Jump started backwards

I was on my way to work and my car would not start after I stopped at the gas station. One of the helpful people at the station gave me a jump start and I continued to work. I asked one of my co workers to give me a jump to get home and when I started the car there were sparks and a bit of smoke from the battery. We hooked it up right and it will turn over but not start. The fuses are all good, the dash lights come on (service engine soon, check engine and security). We replaced the battery, and the coil assembly (I think that contains the ICM, but not sure). I called the mechanic I normally use and he said it was probably time to buy a replacement car. My friend (the one who hooked it up wrong) thinks it might be fixable, he has some mechanic experience and stated we are getting no spark and the fuel pump will not engage. We hooked up a car scanner to it and it was unable to communicate. Any advice would be helpful.

Sounds like a fuseable link blew or you fried the cars computer. You need to locate the fuseable link first. I would get a repair manual for it, one that has a good wiring diagram in it.

Hooking up a battery backwards causes all kinds of problems in todays cars. You have to replace and test different components until you find the one(s) that were killed by the mistake. Likely the car’s main computer is fried. That controls so many things including the spark and fuel injection systems that replacing the ECM is where you start. Perhaps you can find one for your car at a salvage yard.

There are fuses, circuit breakers, and all manner of computer chips in your car so it takes awhile to figure out which are OK and which are toast. It can be fixed but it takes time and isn’t going to be cheap.

“a bit of smoke from the battery”

You’re lucky you didn’t end up in the ER or need to use a white cane and learn braille!

I would suspect a blown engine computer and/or blown alternator, just for starters.

Thanks for the replies. I did quite a lot of research on my car and was not able to find a fusible link (though I was able to find a cable that was being referred to as a fusible link cable in some forums). I crawled under the car and verified the cable that some people called the fusible link cable is intact (purple cable in between the starter and alternator). It looks like on this type of car there are two computers (one behind that battery and one under the dash) that need to be paired for the security system to work (not sure if they need to be paired with the key as well), and I am thinking the alternator is toast as well. Very sad.

When a fusible link blows out it can be hard to tell by just looking at it. If that is what you did then you will find out it is really bad if you check it again by either felling the center part of it or measure the voltage across it. Something in the main power buss has opened up and not providing power since you say there are a number of areas not working now.

The data I have to look at shows there is a blue fusible link between the battery and the alternator output, as you stated earlier. Check the voltage across the alternator output and the positive battery post. If you have more then 1 volt across those points then the fusible link is bad. Though a problem there won’t cause the other problems you are having.

The data also shows a fuse labeled IP Battery Fuse in the panel under the hood. If that fuse is bad then things like your door locks and power mirrors won’t work either. Check the other 30 amp fuses there also. Check the voltage across them. If you have more than .2 volt across the fuse then it is bad. If none of those are bad then check to see if voltage is getting to all the fuses in the dash fuse panel while the ignition is ON.

If the computer won’t communicate when hooked to a scan tool and no fuses are blown, it sounds like there’s a good probability that it’s toast, as others have said. I’d try that first, but it may only be the tip of the iceberg.