[OT] 2020 Mazda 3 Problems, Again

Boris snipped-for-privacy@invalid.invalid wrote in news:XnsB3699EC29FF4BBorisinvalidinvalid@157.180.91.226:

Well, maybe the service rep is right about 1). I found 'AI Overview' articles supporting his statements, and this one:

Yes but he's exaggurating it badly. It's short trips of 1-2 miles only every 10 days that can cause problems. I have to remember to run mine (in the driveway is fine) for 15 minutes or so a week if not making any longer trips to avoid the problem.

Trickle charger will fix it. I just got one but haven't set it up yet.

That works well.

The short trip thing makes sense. New cars often have sensors running for a period of time waiting for a signal to unlock, remote start, etc. I know that my car will not remote start if not used in four days.

Never heard of the different driver things though.

Solution is simple. Get her a '68 Chevy that does nto have all the technology.

Ed P snipped-for-privacy@snet.n wrote in news:10bfdr7$3ckr8$ snipped-for-privacy@dont-email.me:

Good choice, but I'd have difficulty deciding between the body style of a '67 or '68 Chevelle SS. And then there's the '67 GTO.

That is not normal and don’t let anyone tell you it is. To me, it sounds like you have a BCM that isn’t going into sleep mode. The BCM, when active, consumes between 0.20-0.25 amps. When in sleep mode, it should drop to

Should not need to use a trickle charger if you use the car every few days. Even a Toyota Prius will still be able to start the engine after *2 months* of no starting. 3 months and the Prius might complain. My wife’s Suzuki Swift (2016) sat unused for 6 months and still started when I needed to use it. It seems that electricals confuse today’s mechanics and electronics confuse them more. Don’t be bluffed by bullshit from them. Is it still under factory warranty? If it is, they’ll bluff you till it’s expired. Unwanted parasitic draw is a problem, the Mazda at the very least needs to have that checked by a competent auto electrician who understand the relevant concepts involved.

Point to note, the Mazda 3 with the start stop technology requires a robust (read:expensive) battery typically of the glass mat type. Don’t cheap out on it else you’ll be subject to a litany of subtle issues. A cheap battery will give the ECM incorrect (low) voltage readings and the ECM will refuse to start the engine. Remember, that button on the dash doesn’t start the engine, it only alerts the ECM to the fact that you want it to start. If everything checks out to the ECUs satisfaction, inc battery voltage, the

Also note, both the starter and the alternator are under complete computer control, ensure those two items are up to snuff. Test the alternator under a heavy load, should go to max output. Used to use a bank of headlight globes back in the day to provide a load.

Cars have built in learning ability in engines and transmissions for sure. They are adaptive and the driver who drives the car most will determine the

Idling your car for long periods is not healthy for the engine. Because of modern fuel standards which the government has imposed on car manufacturers, they use every possible method to reduce fuel consumption.

Your car idles at a lower RPM than older cars did and this has the effect of not circulating the oil properly into the top end (head). Also piston rings have much less tension so blow-by gasses and fuel get past them into the crankcase oil. This causes oil dilution due to fuel getting mixed with the oil. Newer Hondas are notorious for this.

Cars have to be driven up to operating temperature periodically to burn off carbon in the combustion chamber and fuel in the oil. Idling does not help the engine reach operating temperatures.

Xeno snipped-for-privacy@optusnet.com.au> wrote in news: snipped-for-privacy@mid.individual.net:

Thanks for the reply.

I spoke with the service rep today, and he assured me that the BCM and ECM checked out fine, and insisted that the car just isn't driven enough, on a daily basis, to replenish the battery's charge. I told him that the drive to bring the car from my daughter's home to his shop was a 50 minute freeway drive. He said when the battery was tested upon arrival at his shop, it was only 55% charged, because it was depleted from short trips and the 50 minute drive was not enough to fully recharge the battery, but otherwise the battery was good. He said he has many older customers that also drive very little with the same problem. He tells them to use a trickle charger.

My daughter's car is a 2020, and the original battery lasted only three years. The car wouldn't start and the battery wouldn't hold a charge. I installed a second, appropriate battery in 2023. In July of this year, the second battery kept dying, and the dealer replaced it. So this is the third battery in five years, with similar problems.

I asked the parts man at my local NAPA supply store what he thought about all of this. He also thinks the battery should not be going dead all the time, regardless of driving habits, and suspects parasitic draining. If the BCM is not turning off all of the accessories after 30 seconds or so, pull every fuse, one at a time.

I found a shop that does electrical detective work, and will visit them when I get a chance, but that won't be for a few weeks. When I do, I'll report back here.

By the way, her Mazda does not have that auto stop/start, thank goodness.

Comment/rant: With all the creature comfort features, all the computerization and sensors on new(er)cars these days, it's hard to believe that engineers didn't compensate for the extra load on batteries. Who wants to buy a new car and have to worry about keeping the battery charged? Does an older, retired couple who drives five miles to the grocery store once or twice a week know how or want to have to trickle charge their car? I guess this is progress.

Thanks for reading this far.

I participate in a couple of car forums. This is a too common situation for cars not used often. My car, for example, has built in communications and it is always looking for a signal to do something, such as remote start. After 4 days, it shuts down. I've not tried it, but allegedly it can go over a week and start OK.

Battery tender seems to be the key for those of limited use. Easy enough if you park in the garage, not so much on the street. May be something you should look into. A Battery Tender is more sophisticated than a trickle charger.

FWIW, my 2015 diesel Citroen Berlingo is used once a week for a 10 mile round trip, and maybe three times a year for 300 mile round trips. No more than 2000 miles a year for the past 5 years of my ownership. Never failed to start. Replaced the original 10 year old battery a few months ago as a precaution.

Ed P snipped-for-privacy@snet.n wrote in news:10bjqm5$h5r8$ snipped-for-privacy@dont-email.me:

I ordered and received today, a Battery Tender. She'll use it until we get this cleared up.

RJH snipped-for-privacy@gmx.com wrote in news:10bjri1$hlnm$ snipped-for-privacy@dont-email.me:

I guess the older the vehicle, the fewer 'gadgets', the less continuous draw on the battery.

My 2013 Mazda CX9, 150k miles, often sits for weeks, last year for three weeks, and starts right up. It's on its second battery.

My 2013 Dodge Charger, 33k miles, rarely driven, can sit for months and still start. Still has original battery.

My 2010 Ford Escape, 100k miles, also sits for weeks and starts fine. It's on its second battery.

badgolferman snipped-for-privacy@gmail.com wrote in news:10bjogj$gldq$ snipped-for-privacy@dont-email.me:

Thank you. When my daughter comes home with the dealer invoice, I'll check to see if they referred to that bulletin. But, usually the invoices are not very informative.

My 2002 Honda Goldwing motorcycle was having a problem where sometimes it just wouldn't start. The starter would crank and the battery was fine. Sometimes after repeated cranking for long periods it would finally begrudgingly fire up.

I took it to the local authorized Honda Powersports service repair shop where I get all my maintenance done. They told me they couldn't find anything wrong and that it started up just fine for them. No ECU codes. Bring it back when it's broken. The problem is it breaks down when I'm away from home.

I called the authorized Honda Powersports service repair shop in the next city over and talked to the service guy who's been there for 40 years. He said he knows exactly what it is and has fixed many of them. The crankshaft position sensor, aka pulse generator. Apparently it's used for timing of the spark plugs and fuel injectors. I took it there and a few days later he called me back and said come get it. It was a $50 part and $800 labor to tear the bike apart and put it back together. So far there has been no issue. I'm hoping it stays that way since I'm going on a six day trip with my gang next week.

ZOOM ZOOM. It's a Mazda - - - -