Jump started then warning lights...

So, the 2007 CX-9 was sitting for a few weeks and would not crank (accessories did not even come on). I pulled the NC Miata around, but it had not been cranked for a while either, so I did not want to immediately shut it off. I should have just gone for a short drive, but instead I hooked up the jumper cables (in the correct order) with the miata running... I let it run for a while and revved it to about 2k rpm for a few minutes, tried to crank the cx-9, but had to wait a few more minutes and then it fired right up... Here is the problem... now the turn signals in the CX-9 will not work (no ding or indicator light when door opened either), but it does cut the switch back to center if I engage the stalk and then go around a corner. The fog lights and emergency flashers do not work either (nor does the rear wiper, but the washer fluid does work). And, some warning lights are staying on: TCS OFF, the TCS/DSC (little swerving vehicle one at the top), TPMS, oil pressure, KEY, and the brake system warning light... What have I done!? I did forget to unplug my wife's cell phone charger. Everything else seems to work, windows, navi, radio, cluster, etc... No stored codes when checked with Torque lite...

Everything I read obviously says to turn the booster car off and then on again after the cables are on, but I always thought that was a safety thing... and none of the dire warnings and things to avoid address the engine running while cables are hooked up, and I can't find anything that says what harm it might cause... I thought I had recollection of the good ol' boys around here doing it like that. If I did fry a computer or something I sure hope it can be replaced... I read something in the manual about using a 24v booster (which I did NOT do) and causing irreparable damage... needless to say that did not help my anxiety!

Thanks all!
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First thing I would try is putting a new battery (or one that you know is good) in. Low voltage batteries can trip a lot of error codes sometimes.
2010 CX-9 GT
You are probably fine...

I just had a similar situation. Car sat so long the battery was nearly dead. The car started (barely) and every warning light was on. Turned it off, then it wouldn't even crank.

I have a trickle charger, I hooked it up and charged the battery for a day. Everything is fine now.
Thanks guys. I did crank it a couple times after that and let it run a while each time; good chance youri is right; we bought it around the end of summer and I don't know how old the battery is, and I haven't checked for a date or tested it. My dad has a charger, so I can try that first, but it is good to know it is likely not damaged...
Long story short, I got a new battery (that I probably didn't need), put it in the cx-9, had all the same lights/problems as described above, drove it around hoping it would reset (checked for a cleared non existent codes again), drove it around a little more with no change, kept an eye on the charge for a few days, thought it was okay, let it sit a couple weeks, and bam, the new battery was dead.

So, I got the battery tender, charged it back up and started removing the negative battery cable when not in use; even with a full charge I have all the same lights and problems as before. I don't see evidence of rodents, but I guess I need to find my old test light, see if it works, and work my way through the fuse box? Any other ideas are welcome!

Side note: when sitting in the hot summer sun I have noticed a faint gas smell around the car... electrical problems and gas fumes, good combination, eh!? Not sure if it is from under the car or the engine bay. How concerned should I be about that? I need to take it and put some gas in. Back when parked it was between a 1/2 and 3/4 tank, now it is around 1/4 and the gas is from late February, so I should pick up some stabilizer too.

Thanks guys!
2010 CX-9 GT
It sounds like the body control module might be fried. Several of the failures you are describing can be caused by the BCM (warning lights, non functional accessories, battery drain). You can unplug the BCM and see if it cures the battery drain issue. If that does the trick it needs replacing and will probably fix the other issues.
Many thanks jal42! I am reading about that now, and honestly I hope you are right! I will check it out (still need to look up how to access it), but here are some resources for anyone else who might stumble on this, and of course, I will update this thread.

edit: instead of waiting for the battery to drain would it work to use my test light to check for a drain as per the beginning of this video?

edit 2: I don't claim to be very smart; can I crank the car while the BCM is unplugged?

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2010 CX-9 GT
Yes you could check the circuit to see if the BCM is a current draw.

I don't know if you can crank the car or not.
Chapter 3:

I have some good anecdotal evidence that the BCM is fried
, and I just hope everything else is good. A few days ago I decided to look at the access to the BCM and realized that the driver footwell was essentially a puddle, and though there is no smell yet there is some white fuzz growing in the area. I removed the trim at the edge of the carpet and commenced soaking up all the water and squeezing all I could out of the carpet and sound insulation. I got it pretty good and left it raised up to get air underneath it. On sunny days I am opening it some to get some air and finish drying, then I will clean it up and probably treat with Concrobium. I should have noticed the water sooner; it seems like I saw some condensation on the inside of the windshield a while back (after 3 inches of rain) and should have been suspicious.

Anyway, I took some old string trimmer string and tried to fish it down through the sunroof drain, but it seemed to get stuck on both sides, like there is a blockage (I did not pour more water in since it seems pretty clear... I may try that, but I've been busy). I got a couple feet in on the driver side and a little more on the passenger. I might try again with something lower gauge and/or stiffer, and if that does work I guess I might have to resort to this (my wife was not keen on my joke about siliconing it shut and ripping the controls out):
2006-2015 Mazda CX-9 Sunroof Water Leak Repair - How To - Imgur
I also had a thought that maybe I could use an air compressor and a short piece of flexible hose (shove one end on the air nozzle and the other end into the sunroof drain access) and try to blast some dirt out... Thoughts? (It sounds like maybe the dealers and DIYers use compressed air, and I know it is safe for some cars, but not others, like in my e46 I am pretty sure it can blow the junction of hoses apart, but looking at the diagram I think the CX-9 is just a once piece deal, so maybe it is okay to try?) For now I have a tarp across the car during any rain...

Finally, it looks like it will not be hard to get a used BCM with a short warranty from Ebay. I may or may not even bother with more diagnosis before buying one (already threw money at a battery I didn't need... why not throw good money after bad!?). From VIN decoders and lists of standard equipment I am pretty sure I need one for a car WITH a burglar alarm (07 Grand Touring). I do have a red dash flash (but so does my NC miata and I don't think it has an alarm). I could check the owner's manual, but it is in the car and it's late (maybe I will look tomorrow). That is a long-winded way of saying is it safe to assume I need a BCM for a car with an alarm?
2010 CX-9 GT
I think the safest thing is to copy the part number off the existing BCM and match it. I have the dash light too, but I didn't pay for an alarm.

On the drain, you can try a vacuum first before the compressed air if you are worried about blowing fittings and hoses apart. The condensate drain on these cars sometimes clogs up and a vacuum sometimes works when compressed air doesn't. You will have to rig something up to hook a shop vac up to a small tube.
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Good idea on both fronts... I was looking right at the BCM and did not think to grab the part number... brilliant! I think the shop vac idea is good too and I appreciate the speedy advice... I need to get more sleep!