2017 Taco Battery Always Dead

I bought my 2017 Tacoma brand new and had the dealership lift it and add the aftermarket stereo. Ever since I bought the vehicle it has been a slow or no starter.

Toyota has replaced the battery 3 times. The dealership indicates the vehicle show no additional draw on the battery at rest over about 20ma. We live in Arizona so I suppose the heat can be hard on the battery. But I can't drive it unless I jump it at every stop. Dealership says I don't drive it enough. Jeez I wonder why. Also told me the alternator in the new vehicles doesn't kick in till after 35mph. I live in a city, and close to work. Am I crazy or did I get a lemon? There are trucks at the dealership only get driven around the block for test drives and they fire right up.

 

How often do you drive it?
What distance do you drive?
What speed do you drive?

 

https://youtu.be/COJr7OB23Hw

 

10 miles per day or more. Our Mercedes doesn't have this issue. I drive the speed limits 35-45mph. But when I open the door after a week or so I don't even have enough battery to illuminate the dashboard. I'd drive it more if I didn't have to use the portable jumper at every stop.

 

Toyota uses total junk batteries. when mine died i skipped the warranty replacement because i expected it would go like it has for you. I'm not sure 100% you've had 3 failing junk batteries, but if it was me i would spend some $ and replace it with a good one.

 

Toyota replaced the battery 6 weeks ago. Alternator tests fine, and drain is minimal. If they have junk batteries from stock, why don't their cars on the lot have to be jumped.

 

Toyota OE batteries aren't great, but it doesn't sound like you are driving it long enough or fast enough for the alternator to provide a full charge.
Cars on the lots often do have to be jumped and/or batteries replaced, however, you never know how long the inventory is sitting. They could also be idling them for long periods of time. Each dealership has their own battery maintenance plans.

 

Without what?

 

Sometimes we’ll after the computers shut down a module can wake up in the canbus and cause a draw. Or a relay sticks or there is a short that isn’t always shorted. Lots of things can happen. Get a good multimeter and do a amp test and see for yourself what the draw is. Most new cars don’t draw .013 amps. It’s usually .020-.035

 

Also if you're jumping the battery to get the cranking amps to the desired point, RATHER than trickle charging to provide full charge/state of health, you're setting yourself up for failure.
Would recommend a) driving on the highway once a week for 20-30 minutes or b) investing in a trickle charger and maintaining the battery once a week to full state of charge/health.

 

Why do my other cars work just fine?

 

Depends on what they are. You mentioned Mercedes - they typically use AGM batteries which allow for deep discharge and their alternator spec (speed / distance required for full charge) may be very different.
Every vehicle is designed differently.

 

You say you drive 10 miles every day, but then say you let it sit for a week on end? Which is it? My first guess would be improper wiring of the aftermarket stereo you mention.

When you do the draw test as mentioned above make sure you check all leads that may be attached to the battery post, not just the main one. Also, make sure everything is nice and tight when you put it back together

 

ALL STEREO EQUIPMENT IS (disconnected from the battery at the moment).

 

I would also check the contact points, I am on my third Tacoma, and have had to change the contacts on every one. The stock contacts for the battery posts are not very good, and typically result in a loose connection that will draw your battery down, and potentially ruin the cells. Worth looking at, and a cheap fix. I use a marine clamp and solder on copper ends. Have not had any issues after that.

 

What size amp (if any) are you running on the aftermarket stereo system?

 

I average 10-20 miles per day. Rarely have to get on a freeway. Is the a ECU chip mod I can override to get the alternator running all the time?

 

Stereo is disconnected at the moment so I can actually drive it after a jump.

 

I have disconnected all of my aftermarket stereo equipment so that I can drive the truck. I just hate jumping at every time I have to stop somewhere. I've owned Tacoma's and and 4runners my entire life and never had these types of issues.