Start/Stop with bad battery stupid question... Plz help!

[JeffKeryk]

I was wondering... Our '21 RX450h uses start stop, and is pretty seamless, at least better than some others.
So if the battery was dead and if I jump box started it, what happens when I drive?
Does the gas engine stop at stoplights? What if it won't restart? Is the car bricked?

Thanks for your help!

 

[Warstud]

Good question - but when it stops I think it just stops a few of the cylinders from firing . Solution is to take the jump box with you in case Im wrong .

 

[BornSlippy]

The engine stops with one of cylinders at TDC. It actually restarts by injecting fuel and firing the spark plug. It doesn't rely on the starter.

 

[JTK]

I know on the GM products I have with stop/start, the system monitors the battery(s) and will disable stop/start if voltage falls below threshold, the MIL is on, etc.

Most of these systems rely 100% on the starter, re-starting the vehicle.

 

[Escape08]

See if you have the option to disable S/S system. I disabled it in the menu option on my Jag

 

[Nukeman7]

I have read on other forums that the auto start-stop system will disable itself once the battery charge become too low. This Lexus thread says it will show "system charging" on the display screen when this happens.

Lexus Start-Stop with Low Battery Charge

 

[Vercingetorix]

No separate battery for start stop?

 

[Jetronic]

I was wondering... Our '21 RX450h uses start stop, and is pretty seamless, at least better than some others.
So if the battery was dead and if I jump box started it, what happens when I drive?
Does the gas engine stop at stoplights? What if it won't restart? Is the car bricked?

Thanks for your help!

The S/S doesn't stop the engine with a low charge in the battery or if the battery has been disconnected recently. If you tried starting with a low battery it would look the same as the battery getting disconnected.

 

[LongTime_Lurker]

Are you messing with us Jeffrey?

 

[BMWTurboDzl]

I was wondering... Our '21 RX450h uses start stop, and is pretty seamless, at least better than some others.
So if the battery was dead and if I jump box started it, what happens when I drive?
Does the gas engine stop at stoplights? What if it won't restart? Is the car bricked?

Thanks for your help!

It should only function if the battery has sufficient charge at least that's how BMW does it

 

[Zee09]

My VW won't go into stop start mode unless it's optimally charged.

I didn't use it for a month and it took several trips to activate again. Like 50 miles or so.

 

[ctechbob]

The engine stops with one of cylinders at TDC. It actually restarts by injecting fuel and firing the spark plug. It doesn't rely on the starter.

Are you sure about that? Haven't checked lately, but I know Mazda had worked on that for years and never got it to work properly.

 

[JeffKeryk]

Thanks for all the replies; this helps. We haven't used the RX much; it only has 2700 miles on the clock. Wifey and I went and swapped it out for the TSX yesterday. Nice SUV, if you are into that kinda vehicle. I had a 1A battery minder on it, but the original battery bit the dust a while back. Lessons learned were to get a higher amp charger and connect it directly to the battery. I had it connected to a lead under the hood; the battery is in the boot.

Need to use it more.

 

[KrisZ]

We are talking about a Toyota Hybrid system here. If the battery is dead, the car will not move. That’s how these hybrids are set up.

 

[BornSlippy]

Are you sure about that? Haven't checked lately, but I know Mazda had worked on that for years and never got it to work properly.

I am fairly certain. We owned a 2022 Highlander 3.6 V6. I remember researching the life expectancy of the starter on these stop/start vehicles and that's the information I found. It sounds different restarting after taking your foot off the brake versus when you push the start button.

 

[ctechbob]

I am fairly certain. We owned a 2022 Highlander 3.6 V6. I remember researching the life expectancy of the starter on these stop/start vehicles and that's the information I found. It sounds different restarting after taking your foot off the brake versus when you push the start button.

I know they generally have different starters, or use the hybrid motors to spin them if they are hybrid, but I was under the impression no one got that system to work yet.

Have any links to where you saw that? I'd like to read up on it.

 

[BornSlippy]

I know they generally have different starters, or use the hybrid motors to spin them if they are hybrid, but I was under the impression no one got that system to work yet.

Have any links to where you saw that? I'd like to read up on it.

I have been looking since you asked the question. I haven't been able to find where I read that yet.

 

[ctechbob]

I have been looking since you asked the question. I haven't been able to find where I read that yet.

Lol, sounds about like my luck.

I think as I get older, my brain makes up crap just to keep me re-researching on stuff I swore I knew once.

 

[BornSlippy]

Lol, sounds about like my luck.

I think as I get older, my brain makes up crap just to keep me re-researching on stuff I swore I knew once.

That's not out of the realm of possibility here either.

It may be peculiar to the 2GR-FKS because of the Atkinson Cycle on that engine.

 

[The Critic]

Guys, this is a real hybrid. The 12V battery only powers the electronics.