Won't start when cold

So I started having trouble with my 2020 Tacoma.

When it's been below -15oc lately my car won't start at all or has a lot of trouble starting.

I have taken it in twice to the Toyota dealer. They replaced the battery but still having the same problem. They said they can't find anything wrong with it?

A couple of times it's started fine with remote start But when I've gotten in it and tried to restart after running for 10 mins it wouldn't restart and I've had to jump it.

Sometimes it will start fine but the heater display temp is really dim and barely visable and the touchscreen will just freeze or take forever to start.
Any suggestions I can take to the dealer for them to check while it's still under warranty?

 

That sounds like a bad battery even though they replaced it, or said they did. If a truck runs then you restart and have to jump it sounds like the battery is not holding a charge. Next time it does that use a multimeter and see what the voltage is. Also check to see that the connections are all tight. I have had my truck way colder than that and it cranks just fine.

 

Welcome 2 TW!!!!

did you ask what the cca are on your new battery? get a diehard battery ASAP

 

Also check that the charging system is charging the battery adequately. If it's not holding up the battery, you get a weak battery and all the problems that go with it.

 

Is it cranking? Slow? Normal?

 

Are these your symptoms:
- will start fine on auto start and run normal
- when you open the door and try to start it again, it just cranks and cranks with good voltage (in other words, it does not crank slowly)
- when it does want to start, does it have a hard time getting to idle

Your head unit being dim and slow is most likely because of the cold.

 

For extreme cold like that you may want to upgrade to a battery with a larger capacity/CCA rating.

 

Not exactly extreme cold, as -15c is +5F. Hope OP got this figured out. -25F here as we speak, and my stock 2021 does not hestitate.

 

My stock 4 year old battery was just fine at -20C. The screen was a bit slow for a few minutes but that’s about it.

 

Have you done any electrical mods to the truck that could be drawing power with it off?

 

Assuming the 2nd battery is good, make sure that all the battery cable connections to the chassis grounds and starter are tight. Voltage losses are greater at higher amps and lower temps.

 

Battery -> Alternator -> Starter would be my point of attack. As the cold makes all these work a little harder. What does it sound like when it won't start? I had a failing starter few years ago, that would act normal except in the very cold, when it need a few extra cranks to get it started.

Also helps to have a decent amount of gas in the tank to prevent freezing.

 

OP may need a bit of basic maintenance.

First is the battery, what is the CCA rating on it? Suggest to be well above 600 CCA, the more the better.
Has the MAF and throttle body been cleaned? If not, it won't hurt.'
Has the air filter been changed? If not, won't hurt.
Spark plugs. What is their condition? Time to change?
Oil Viscosity. Is it the correct viscosity for the temperature?
Parasitic current draw on the battery? Be sure to turn off all accessories before starting. Give the starter all the current and voltage it wants.