Battery connected backwards on C6. Where to start?
 

I made one of the most stupid mistakes in my life this past weekend. I went to install my optima red top in place of the AC Delco that had just given up in my 08 C6 and I didnt pay close enough attention, didnt realize the Optima wasnt situated the same way the AC Delco was, and I ended up connecting + to - and - to + terminals for a few seconds. The car honked, windshield wipers turned on, smoke started coming up from the engine bay and a second later I heard a loud "POP" sound coming from under the hood somewhere.

Once I correctly installed the battery, the car started right up, however there are a few major problems now. First off, I found that the radio fuse blew and the radio was dead. After replacing the fuse, the radio head unit turns on, but no sound comes out of any speakers. Secondly, my AC does not blow at all. The HVAC controls light up, but that is all. Thirdly, and most importantly, I got a warning on the cluster to "Service Charging System" and the alternator is definitely not working. Had to drive the car about 30 minutes round trip and it drives fine, except for the battery voltage continually dropped until the car died (luckily right in front of my garage)

Where should I start looking for the items I need to replace? I assume I have blown out the fusible links, and possibly the alternator itself. Is there another fuse panel as well? (other than the one on passenger floorboard?)

How would you guys go about diagnosing/fixing the problem now? Any help or advice you can give will be GREATLY appreciated. I am very depressed over my stupidity, please dont remind me of how dumb it was because I already know and feeel terrible.

Thank you in advance for any possible advice

Alternator is fried, that was the smoke. Several fuses are fried in the foot well fuse box. You might have a couple fried in the engine bay fuse box.

Elmer

I have an optima yellow top in my 2008 c6 and the terminals are on the correct side. Someone gave you the wrong battery does your bat model number have an R next to it? That stands for reverse posts. That's how it is on my optima in my Mini Cooper.

I would start by checking all the fuses. If you live near Milwaukee, I would be check you alternator for you.

thank you! Just found a burnt out fuse for HVAC and the amplifier in the under hood fuse box. Hopefully those fuses will resolve those issues. Now for the alternator, should I just go ahead and replace it or should I test it somehow first? 99% sure youre right on the money though. Also, is there likely any wire damage or might I luck out by just replacing the alternator and fuses?
that makes perfect sense, thank you
thank you very much for the offer, but unfortunately im nowhere near there. How would I go about checking it before replacing though?

Thank you very much for the help guys! Promise not to be so careless again in the future....

With the service charging system warning light on, I would check the cheapest fix first -- your solenoid. Reach up and wiggle the top terminal as you might have fried it. ( the smoke you saw may have orginated from it )

as for the alternator --- it is a 145amp ( if stock ) ... I would suggest doing an upgrade anyways... but check it regardless. I put in a 200 amp aftermarket as the stock is barely adequate for the corvette's power consumption.

If you are in So Cal, I am willing to help you out and check everything.

BTW, I speak from experience. I had a tech do the same thing to my car. He simply put the battery in backwards and connected to the wrong terminals.

Elmer

i have nothing good to say.... but wow.... you seem lucky so far, i would expect everything to be fried..

Which solenoid are you referring to exactly? And which terminal?

Thanks for the tip on the alternator, if it needs replacement I will definitely take your advice on that. I live in the Riverside/Corona area of SoCal, and I definitely would appreciate some help fixing this! I'm going to PM you.


After a more thorough inspection this afternoon, I found that the fuses for the HVAC and Amp in the underhood fuse box were blown, so I just got replacements for those and i'm hoping that will resolve those issues. As far as the charging system, I spotted a wire, probably 8ga or 6ga, that appears to be coming off of the starter down in the passenger side of the engine compartment, next to the catalytic converter, which looks like it has burned and split open. The wires inside are black and the insulation is melted off of the wiring itself. This is the area that the smoke and the pop sound came from, and im pretty certain that this wire is, or at least is part of, my problem.

It was too late to call the dealer, but I went to O'reilly's to see if they could look up a fusible link that attached to the starter or in that area at all, but they werent able to pull anything up.

Any ideas what this wire is and how I should go about replacing it?

thanks for the help Elmer, did you have any issues with the wire I described above? Im not certain that the alternator didnt smoke, but I am sure that at least the majority of the smoke in my case came from the melted wire

The alternator went up like a flashbulb. I was screaming at him to pull the wire and he responded immediately but it was "poof" and gone. If you don't see any output, the dog is dead. If you suspect the wire, run a shunt around it to test or pull it off at the connections and "ohm" it for continuity.

Elmer

Arent the posts on the battery a different size so you can not connect the cables the wrong way?

Certen things in the C5 & C6 are HOT at ALL TIMES and there are things that are SWITCHED HOT.

I agree. Start with all the things that are HOT AT ALL TIMES in the battery B+ circuit:
Alternator
ECU
BCM

If you cooked a fuseable link, you need to obtain a new one from the dealer and solder it in and heat shrink the soldered wires. You cna probably find fusable links in the correct amperage on the internet Just GOOGLE fuseable links or check the digikey website as they have a ton of electrical components.

The alternator can be repaired by an alternator repair shop. Most likely the diodes and regulator is fried.

Once you get the main B= Power sorted ot, obtain a Diagnostic Scanner and start reading and correcting the reported DTCs.

BC

That sounds like you fried a fuseable link. I would check all wires/fuseable links/fuses first. You may have gotten lucky and only fried the fl which prevented damage to the alternator etc.

If I recall correctly there are two (maybe three) fuseable links wired-in the vicinity of the alternator/starter components. Bill Curlee probably knows this and where they are located.

Theres one FUSEABLE LINK for the generator and one actual fuse for the starter SOLENOID control circuit:

http://img.photobucket.com/albums/v4...Schematic2.gif

http://img.photobucket.com/albums/v4...ingCircuit.gif

I have an alternater out of my 2008 if you need one I will make you a good deal on it, let me know.

you can take the alternator to your local auto parts store and they can test it for free. That way you will know for sure.

:iagree:

Can do that while you are getting/waiting for a fusible link. The diodes in the alternator should be fine since the fusible link went first. No way to know about the regulator or the circuit for the generator turn on signal in the ECM. If the alternator checks out on their tester you may need a new ECM.

Bill

First off, thanks again for everybody's help!

Bingo! The wire I descrived earlier was in fact the fusible link. I disconnected it from the starter, and was able to solder/heatshrink another section of FL in and voila, problem solved! Car is running like a champ and holding a steady 13.9 volts now. Well, I should say most of my problems solved at least, stereo and chimes are still muted, thinking my Bose amp is fried now.
The alternator turned out to be fine when I had it tested, putting out 14.55 amps, so I got lucky with that for sure. Thanks anyways though

Im very lucky, now my only issue is to get the sound fixed, and im pretty certain its the amp. The fuse for the radio and amp both blew out, sO hopefully replacing the amp will be the end of this fiasco for me.

Thanks again everyone!

final update on this subject:

took the amp out today, took the back off, and found a small burn mark where one connection had failed on the upper right corner of the board. Took it out, repaired the connection with solder and voila, good as new! Re-indexed the windows, and now, FINALLY, I am back to 100%. The help I got here definitely saved me time and pointed me in the right direction :thumbs:

So, to recap. Connecting my battery backwards caused the fusible link attached to the starter to blow, my BOSE amplifier was damaged causing ALL sound to stop, along with the radio fuse in the passenger footwell panel, the HVAC fuse in the engine bay, and the amplifier fuse in the engine bay. Hopefully this will help someone in the future!