Car randomly wont start, happened 3-4 times in the past week. Do I need a new battery

[MilkyWitness]

2019 BRZ, my car has been acting strange.

It sometimes wont start. It is push button, but I will push the button and I will see some lights on the dash turn on and hear some clicks and then it wont start. Then I try again, and it'll be totally dead, no clicks, no lights, nothing. I then open the hood and I will hear a weird buzzing or electrical sound coming from the passenger side of the engine bay. I will remove the negative terminal from the battery, wait a few moments then reconnect it. Then the car starts just fine when I do that.

I went to Oreilys and they battery tested it and said it was fine. I checked myself with a multimeter and after being parked all night it was at 12.8V turned off, I turned it on and it dipped to 10.71v but started.

I will keep my multimeter in my car incase it dies again and test it then and see what happens, but I just don't understand why it randomly dies. It has done it 3-4 times in the past week.

It hasn't been dead when I start after stopping all night, but it has only ever died after having driven it. It has died after driving it for 15 or so minutes, parking, turning it off, going into a store, coming back out and its dead. It has also died after driving nearly a full tank of gas on the interstate, parking at a gas station, filling up, starting, and its dead.

I have sanded and cleaned the terminals but that didn't do anything and it has died since then. They weren't even really dirty, and they were nice and tight too.

Very confused.

So my question is for now is 10.71v still okay to cold start an engine? What else should I do to diagnose this issue? It hasn't died for a couple days so I am wondering if itll happen again, what should I do? Should I use a multimeter on the battery when it dies again and see whats going on if that helps?

Not sure if the alternator is bad, I don't know how to test it but I could watch a youtube on that. Should I do that?

tl;dr car battery tested at 12.8v cold, 10.71v dip when starting, will randomly not turn on when I start it and hear some clicking, then nothing at all. Removing and reconnecting negative battery terminal fixes it and I can start it just fine. This has happened a few times in the past week when trying to start my car. With car running battery is at 14.2v. Stock original battery and car has 38k miles on it.

[BlOody_BoOger]

Originally Posted by MilkyWitness

2019 BRZ, my car has been acting strange.

It sometimes wont start. It is push button, but I will push the button and I will see some lights on the dash turn on and hear some clicks and then it wont start. Then I try again, and it'll be totally dead, no clicks, no lights, nothing. I then open the hood and I will hear a weird buzzing or electrical sound coming from the passenger side of the engine bay. I will remove the negative terminal from the battery, wait a few moments then reconnect it. Then the car starts just fine when I do that.

I went to Oreilys and they battery tested it and said it was fine. I checked myself with a multimeter and after being parked all night it was at 12.8V turned off, I turned it on and it dipped to 10.71v but started.

I will keep my multimeter in my car incase it dies again and test it then and see what happens, but I just don't understand why it randomly dies. It has done it 3-4 times in the past week.

It hasn't been dead when I start after stopping all night, but it has only ever died after having driven it. It has died after driving it for 15 or so minutes, parking, turning it off, going into a store, coming back out and its dead. It has also died after driving nearly a full tank of gas on the interstate, parking at a gas station, filling up, starting, and its dead.

I have sanded and cleaned the terminals but that didn't do anything and it has died since then. They weren't even really dirty, and they were nice and tight too.

Very confused.

So my question is for now is 10.71v still okay to cold start an engine? What else should I do to diagnose this issue? It hasn't died for a couple days so I am wondering if itll happen again, what should I do? Should I use a multimeter on the battery when it dies again and see whats going on if that helps?

Not sure if the alternator is bad, I don't know how to test it but I could watch a youtube on that. Should I do that?

tl;dr car battery tested at 12.8v cold, 10.71v dip when starting, will randomly not turn on when I start it and hear some clicking, then nothing at all. Removing and reconnecting negative battery terminal fixes it and I can start it just fine. This has happened a few times in the past week when trying to start my car. With car running battery is at 14.2v. Stock original battery and car has 38k miles on it.

Do you have to hit the brake for it to crank on?

Sent from my IN2017 using Tapatalk

[MilkyWitness]

Originally Posted by BlOody_BoOger

Do you have to hit the brake for it to crank on?

Sent from my IN2017 using Tapatalk

I am a manual so no just the clutch

[BlOody_BoOger]

Originally Posted by MilkyWitness

I am a manual so no just the clutch

Ok I think I know what your problem is let me post a video real quick

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[tomm.brz]

check the clutch switches, there are 2 of them actually near the pedal

[BlOody_BoOger]

Originally Posted by MilkyWitness

I am a manual so no just the clutch

Sent from my IN2017 using Tapatalk

[MilkyWitness]

Originally Posted by BlOody_BoOger

Ok I think I know what your problem is let me post a video real quick

Sent from my IN2017 using Tapatalk

Originally Posted by tomm.brz

check the clutch switches, there are 2 of them actually near the pedal

I actually do hear a weird clicking noise when starting from a stop with my clutch while the car is on

[MilkyWitness]

Originally Posted by BlOody_BoOger

Sent from my IN2017 using Tapatalk

Okay I just went into my car and saw that button, pretty hard to get to. When the clutch is fully pushed in, the switch is not fully pressed, I can push it in further if I use my knife to get to it. I'll have to see if I can get something on there to be able to push it fully in, its really really hard to get to on my car for some reason

[BlOody_BoOger]

Originally Posted by MilkyWitness

Okay I just went into my car and saw that button, pretty hard to get to. When the clutch is fully pushed in, the switch is not fully pressed, I can push it in further if I use my knife to get to it. I'll have to see if I can get something on there to be able to push it fully in, its really really hard to get to on my car for some reason

Yea it's hard try turning it on a few times pushing it with your finger. Just to rule it out and be sure that's what it is

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[BlOody_BoOger]

Originally Posted by MilkyWitness

Okay I just went into my car and saw that button, pretty hard to get to. When the clutch is fully pushed in, the switch is not fully pressed, I can push it in further if I use my knife to get to it. I'll have to see if I can get something on there to be able to push it fully in, its really really hard to get to on my car for some reason

For my I've learned how to reach it from a seating position lol so now it acts like my kill switch

Sent from my IN2017 using Tapatalk

[Kaotic Lazagna]

Is your car still under warranty? If so, I would take it in.

[RZNT4R]

Originally Posted by MilkyWitness

2019 BRZ, my car has been acting strange.

It sometimes wont start. It is push button, but I will push the button and I will see some lights on the dash turn on and hear some clicks and then it wont start. Then I try again, and it'll be totally dead, no clicks, no lights, nothing. I then open the hood and I will hear a weird buzzing or electrical sound coming from the passenger side of the engine bay. I will remove the negative terminal from the battery, wait a few moments then reconnect it. Then the car starts just fine when I do that.

I went to Oreilys and they battery tested it and said it was fine. I checked myself with a multimeter and after being parked all night it was at 12.8V turned off, I turned it on and it dipped to 10.71v but started.

I will keep my multimeter in my car incase it dies again and test it then and see what happens, but I just don't understand why it randomly dies. It has done it 3-4 times in the past week.

It hasn't been dead when I start after stopping all night, but it has only ever died after having driven it. It has died after driving it for 15 or so minutes, parking, turning it off, going into a store, coming back out and its dead. It has also died after driving nearly a full tank of gas on the interstate, parking at a gas station, filling up, starting, and its dead.

I have sanded and cleaned the terminals but that didn't do anything and it has died since then. They weren't even really dirty, and they were nice and tight too.

Very confused.

So my question is for now is 10.71v still okay to cold start an engine? What else should I do to diagnose this issue? It hasn't died for a couple days so I am wondering if itll happen again, what should I do? Should I use a multimeter on the battery when it dies again and see whats going on if that helps?

Not sure if the alternator is bad, I don't know how to test it but I could watch a youtube on that. Should I do that?

tl;dr car battery tested at 12.8v cold, 10.71v dip when starting, will randomly not turn on when I start it and hear some clicking, then nothing at all. Removing and reconnecting negative battery terminal fixes it and I can start it just fine. This has happened a few times in the past week when trying to start my car. With car running battery is at 14.2v. Stock original battery and car has 38k miles on it.

A clutch switch would not cause voltage issues. 12.8V with the car off is fine, but realistically, a healthy battery would stay above 12V with the ignition on engine not running. Where was this 10.7V measured? Directly on the battery posts? On the battery terminals? On the alternator B+ post and an engine ground? Body ground?

It sounds like you've got a bad ground, since everything goes dead I'd guess the ground bolt on the right shock tower, but depending on where you measured your voltage that does not explain the 10.7V. Batteries can have internal defects, Long ago on an old celica I've had a battery fail on an internal bus bar between cells, and 10.7 is exactly 2.1 volts under 12.8V, and 12V lead acid batteries are made up of 6x2.1V cells. If the guy at Oreilys tested the battery with a small electronic device, that's not worth much salt, test it with a load cell, proper load for this should be over 200 amps, and since you've got a random issue that goes away and comes back, wiggle the battery posts while it's under load, you may have an internal break in the battery that sometimes makes contact and sometimes doesn't, and sometimes makes contact just enough to wake the car up but fails once you start drawing high current with the starter, removing the battery terminal and reinstalling it may move the post just enough to bridge the gap.

[soundman98]

10v while cranking isn't that unheard of...

[RZNT4R]

Yeah fine whatever, 10~ish volts is ok lol

BUT YET!

A clutch switch would not cause

Then I try again, and it'll be totally dead, no clicks, no lights, nothing.

It's almost as if there was a power supply issue! Shocking isn't it!