2008 Toyota Matrix - 4 mo old battery, car DEAD this morning

Problem: Car is completely dead. I went to remotely unlock it this morning in the parking garage, and there were no signs of life. I manually unlocked it, turned the key, and absolutely NO lights activated. No head lights, nada.

After sitting there in mild panic for a minute, I mentally summarized the situation:

  • The battery was replaced in January of this year, so around 4 months ago.
  • There were no doors left open or lights left on. The car hadn’t been driven in 36 hours, but that is normal for it (we’ve left it for longer before, in the winter, and it’s always started fine).
  • The car went in for its last oil change & 90-pt inspection last week (Wednesday). The ONLY repairs the mechanic pointed out, which were mild and therefore deferred until July on the next check up, were breaks needing servicing, possibly a new cabin filter, and also new spark plugs (he hadn’t actually inspected the plugs but since it’s been over a year it’s probably a safe call they need attention).
  • This car had >$5k in repairs done in Feb-Nov 2018, none of which had to do with electrical/battery elements.

So. After reading through relevant threads on this forum, I’ve come to accept that maybe some cables/connections to the battery or fuses are dirty? Or broken?

Troubleshooting I’ve tried:

  • Opening up the hood for a general inspection. I don’t know too much about the guts of the car, but to my eyes everything looked normal. I even lifted up the red cap on the battery and nothing seems corroded.
  • Every combination of turning the key and flicking things etc. Like, really, every combination. Just because on these threads I’ve seen that people have miraculously brought their seemingly dead cars to life by turning dials and what-not.
  • Beyond that, not really sure what else to try?

Any thoughts on this? Right now I am waiting for my Dad to come and try to boost the car, and if that doesn’t work we’re going to tow it to wait overnight at my mechanic’s garage to have it looked at tomorrow.


jump car. check voltage while running. your alternator does not like charging a dead battery though. a real 120v charger would be nice. i am betting you left a light on. 2nd guess? bad battery.

Yes, jump-starting the car is for sure what I’m going to try - also my Dad is bring a volt-meter so we’ll check that out. It’s possible I left a light on - which would be a nice simple reason. Or yeah hopefully the battery was just a bad one in the batch. Thanks!

my wife bought my kid and i a jump pack for xmas. kid used it once but their battery had a bad cell. i returned mine. and bought my kid a new battery. and put it in… oh, she used my credit card to buy the jump packs.

… or a failing alternator.
The OP needs to have a competent mechanic check the alternator’s output.

Yeah I’ll mention that to my mechanic when I see him… In my experience he is the most competent mechanic I’ve gone with, but… now I’m having some doubts? I mean this all might be bad luck but… considering the last inspection was literally less than a week ago it’s a bit strange. It is a 10-year-old car though so… there’s that. Thanks.

The routine inspection that accompanies scheduled maintenance rarely includes a test of alternator output, so he could easily have missed a problem of that nature.

There several possibilities and one requires more information to start sorting them out, including:

  • How often do you drive the car, and how far each time on average? Too many starts for the miles driven, especially night miles, and you may not be giving it a chance to recharge. Have there been changes to your driving habits recently that may explain this?
  • Does your alternator light come on when the ignition switch is turned on, but before it’s turned to the starting position? It should light up initially and go off once the car is started - failure to light initially indicates a charging system problem, possibly a bad alternator diode or a bad connection, etc. (or a problem with the light) which will result a discharged battery after a few hours of operation (less at night with the lights on).
  • Assuming the battery and charging system are healthy, your car may have developed excess “parasitic drain”, which could range from a failure in one of the electrically powered components that remains connected when the ignition is off to a failed or misadjusted trunk or glove box light.
  • Although unlikely, batteries occasionally suffer either due to a manufacturing defect or possibly to excessive charging (you can have someone check your alternator’s output).

Thanks Ken:

  • Between my partner and I we drive the car typically every day, maybe around 25-40km (I’m Canadian haha) on average. I’m not sure the ratio of starts, but the habits seemed fine before this? There have been changes to my habits before this.
  • Absolutely no lights come on at any point when I’m turning the key in the ignition. I’ve tried every combination of turned positions I can think of, and there is 0% activity at any stage.
  • As far as I know there were no lights left on, but it’d be impossible to tell now I guess, as the car is dead.

These are all good things to know for when I talk to my mechanic, thank you!

The alternator light coming on advice pertains to when the battery is charged, not necessarily to your current situation - sorry, I didn’t clarify this.

Ah okay, thanks for clarifying.

Yeah I’m at a loss. As I said in my original post, this car went to the shop a LOT last year, and I became really intimately familiar with all of those specific problems, and I really thought everything would be fine (naive I know), and now this? Honestly just really hoping it’s a bad battery…

Plugs are good for thousands of miles and does this person really know how to jump a vehicle because bad things can happen to the electronics of both vehicles . I don’t jump , for about 25.00 I have a service come with a battery pack to do that.

That’s a near perfect driving pattern to keep the battery charged.

In addition to a bad battery or a failing alternator, you could have a parasitic drain (like the Carbon Tax) somewhere that discharges the battery.

A good mechanic can find that.

In our own experience, my wife’s Nissan Sentra experienced the same but we ended up needing both a new alternator which was not charging enough and replacing an 8 year old battery. My bet is on a parasitic drain or a bad alternator since you nearly new battery is presumably OK…

I’ve jumped my car a few times (back in January the 5-year old battery died in the week of -35C temps we had, understandably), and so has my Dad, with no issues, so yeah I think we can handle it! Thanks though :slight_smile:

If you were having problems with the charging system there would be enough of a charge from the previous trip that you would at least have heard the key chimes etc…
Had the battery been that depleted, the car would have died on the road…not conveniently where you normally park.

I would first check that the glove box light is shutting off when it is closed. Check by opening the glove box and locating the light. Close the glove box and wait a few minutes for the bulb to cool. Then opex the glove box and touch the bulb. If it is hot, the switch is not shutting the light off.

Do the same with any other lights that may come on when a lid is opened. THe trunk, and the hood are two normal locations.

If your dad does come over to jump it and brings a volt meter he can easily check the charging system himself. After jump starting, he should get around 14-14.5 volts across the battery posts with the engine running and the jumpers removed… Any less and there is a problem.


If the battery is dead I suggest you use a charger to try and recharge it with. Allowing the alternator to try and recharge a dead battery puts a lot of strain on the charging system. I would also have the battery capacity and charging system checked out after you get it running again to check things out. Hopefully you just have a bad connection at the battery causing the trouble. Battery connections at times can have a layer of corrosion that you can’t see visually. If the meter shows good voltage at the posts then clean the connections.using a battery post cleaning brush.

When you checked for corrosion on the battery terminals, did you actually remove the cables and check and/or clean them? It’s possible that you can’t see corrosion preventing a good connection.
Did you check the tightness of the connections on the battery? I had a dead car once and that was the problem.
Is the car in park? A car not in park will not start, although it should show some signs of life (don’t ask me how I know this) :slight_smile:.

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Most spark plug replacement intervals are 100,000 miles or more these days. I have not spent $5000 in car maintenance and repairsin my lifetime and I was born before WWII. I guess I save a lot more than I thought doing my own work.

Thanks everyone for your help!

It turned out to be just that the dome light had been on for 36 hours… which is both a relief and a groaner, because I totally had dismissed it as being a possibility, because in the 7 years I’ve had this car I’ve never really turned it on? Or at least it’s just been flicking it on for something at night, but never leaving the “on” mode active. So. The tow mechanic jump-started us and then we drove the car for almost an hour, and it seems to be fine. Still going to get it checked out just to make sure. I still can’t believe that a dome light would drain an almost new battery, but there we go!



That would be good if it turns out to be just the dome light. Many cars will automatically shut off any lights left on after several minutes of parking a car, but not all do. I’ll bet that you’ll be checking that dome light before you exit your car.

You probably have a standard incandescent bulb as a dome light bulb. They use up a lot of electricity creating heat (wasted electricity) besides the light they throw. You could buy a little insurance to cover another inadvertent dome light left on event by replacing the bulb with a cool operating, much more efficient LED equivalent bulb. It should cost only a few dollars. The draw of electricity is much lower with an LED.