[Dayle Frame]

My Bolt is less than three weeks old (1410 miles) and yesterday was another step on the electric car learning curve.

I was 60 miles away from home with 55 miles on the range indicator. I found an CP station that happened to have a pub across the street. While I had a soda and some pie/ice cream, I added 16 miles of range (40 minutes) and headed off. I was on back roads to keep my speed down and maximize range. But it was 30F and getting colder. When the range got below 30 miles, the graphic turned orange. At some point (10 or 15 miles of range) the range indicator stopped counting down and I was alerted to a reduction in power. My acceleration was reduced by my speed was not. It just took longer to get the velocity I needed. Eventually, I got home and plugged her in.

In the morning, my JuiceBox app told me I added 62.78 kWh. That's a lot closer to the bottom than I wanted to go....but I learned what's what as the battery range declines. I'll also be more scrupulous about how much I charge in an emergency when I'm trying to get home.

Dayle

 

[Sourdoughsteve]

Thanks for posting that! Now we know what "power reduced" means. Glad you were able to find that charging station on your route!

 

[specialed]

Yes, power reduced mode is an interesting experience.

 

[moombolt]

Almost seems like we need a switch to put it in reduced power mode, and extend the range

 

[Zoomit]

Almost seems like we need a switch to put it in reduced power mode, and extend the range

You have one. It's called the accelerator pedal!

 

[Bazinga]

Good to note the slower acceleration when you're low on charge. Probably won't affect those who are already light on the pedal, but that seems like a very close call to get stranded.

 

[Electro]

Thanks for posting the experience as it's something that everyone worries about happening.. Thankfully power reduced mode doesn't significantly change anything and appears to just forcefully make you a "hyper miler" lol

 

[Dayle Frame]

Thanks for posting the experience as it's something that everyone worries about happening.. Thankfully power reduced mode doesn't significantly change anything and appears to just forcefully make you a "hyper miler" lol

A good analogy to be sure. Just as every ICE car has a 'low fuel' warning light, the changes at 20 and 10 miles alert you to what's happening. All that said, I've never put more than 14.5 gallons of fuel in the 16 gallon tank on my Accord. I've driven it 25+ miles past when the digital graphic says the tank is empty.....so there's a reserve available. It would be nice to know just how far you can push the Bolt's battery system.

Dayle

 

[devbolt]

A good analogy to be sure. Just as every ICE car has a 'low fuel' warning light, the changes at 20 and 10 miles alert you to what's happening. All that said, I've never put more than 14.5 gallons of fuel in the 16 gallon tank on my Accord. I've driven it 25+ miles past when the digital graphic says the tank is empty.....so there's a reserve available. It would be nice to know just how far you can push the Bolt's battery system.

Dayle

The difference between pushing the limits of your Accord's gas tank and of the Bolt's battery pack is that in the case of the Accord, if you run out of gas, all you need to do is call a tow truck and have some gas delivered to you. With the Bolt, you still to call a tow truck, but then you need the tow truck to take you home or to a public charger, which makes the experiment more cmplicated and inconvenient.

That said, I too would like to know if 0 miles of range is really 0 miles, or if there is a reserve of 10 or 20 miles. But I'm not comfortable testing that yet...

 

[Dayle Frame]

Unfortunately, I'm a chemist and conducting experiments is par for the course. I'll continue to try and figure out where the edge of the envelope is.

One other tidbit of info........below 10 miles of range, the number disappears and you don't see when you actually countdown to zero. I wasn't thinking so I didn't notice what the 'miles driven' number was so I can't report how much I drove after the countdown number disappeared. At some point I'll drain the battery while benignly driving around the block to make a more accurate estimate of total range.

Dayle

 

[Electro]

Would be great if you could catch that on video just so that we can note exactly what happens when it "shuts down" so to speak. What loses power first or what the order of operation is.

 

[Lazyj189]

I can tell you what happens when a Bolt runs out of juice. I ran mine out just 4 miles from my house. It seems that when it gets to the low point and you can no longer see how many miles are left, that there is about 6 miles left before out. I was able to be doing 50MPH when it started going empty, the power meter showing drain will get less and less despite putting the accelerator pedal to the floor and my speed was gradually decreasing. I was able to go about 1/4 to 1/2 mile with the foot to the floor before finding a parking lot to settle in. The gauge showed 0 miles left and the car wouldn't move any more. At this point the car stayed in D, until I opened the door then it went automatically into park and set the park brake. I was able to select N to push it into a spot. Called up my bother and he came and got me. I went home and got my 2003 Suzuki and brought it back. Experiment time. I have a 2000Watt inverter powered by 2 deep cycle batteries in my Suzuki and thought I could hook up the 110V charge cord to get a little charge into the Bolt. However the EVSE charger didn't detect a good ground off the Suzuki and wouldn't charge. I'll fix that later. So I decided that putting the Bolt in N and just pulling it home was my best bet. Had the wife with me so she drove the Suzuki and I steered the Bolt. We went no more than 20MPH the 4 miles to home. Plugged in and charged up for the next morning. However, the next morning I had the Service Vehicle Light on. Checked the codes and they were P0AC4, P0C11, P0C12, P0C13. Car drove fine for 25 miles to my destination where I shut the car off. After restarting from there to get me home the light was off and did not return on a couple other trips. I took to the dealership and explained what I had done. They didn't know as nothing like this has ever happened before. I have a theory that because the drive motor had no power to it while it was being towed in neutral that it detected the motion with the drive motor not functioning and threw the codes. Chevy checked over the car, cleared the codes, test drove it and sent me on my way with an $80 bill. I theorize that if I do this again I intend to have a good ground so my Suzuki can charge the bolt long enough to get the drive motor active and back in D, then I will hook it up and tow it with the Suzuki so it will recharge the batteries again while being towed and there will be no problem, or just call roadside assistance. Questions: I'll try. I'm pretty good at testing things like this in situations like this.

 

[GJETSON]

Unfortunately, I'm a chemist and conducting experiments is par for the course. I'll continue to try and figure out where the edge of the envelope is.

One other tidbit of info........below 10 miles of range, the number disappears and you don't see when you actually countdown to zero. I wasn't thinking so I didn't notice what the 'miles driven' number was so I can't report how much I drove after the countdown number disappeared. At some point I'll drain the battery while benignly driving around the block to make a more accurate estimate of total range.

Dayle

Once you get the message "find a charger' or whatever it was, I tried holding down the check mark button to erase the message, but it wouldn't do it. However, scrolling down to check tire pressure, and then back, got rid of the message, so I again saw my miles and miles/kWh displayed. Same thing when the "power reduced" message comes up. Scroll up or down, and back, and you will again see the numbers. I got down to 14 miles displayed, and I suspect it means it.

 

[TotaledJetta]

Nice work on the experiment. I think I will try to avoid replicating that. Not sure towing it in drive would to charge it would be a good idea, but let us know if you try it. :nerd:

I can tell you what happens when a Bolt runs out of juice. I ran mine out just 4 miles from my house. It seems that when it gets to the low point and you can no longer see how many miles are left, that there is about 6 miles left before out. I was able to be doing 50MPH when it started going empty, the power meter showing drain will get less and less despite putting the accelerator pedal to the floor and my speed was gradually decreasing. I was able to go about 1/4 to 1/2 mile with the foot to the floor before finding a parking lot to settle in. The gauge showed 0 miles left and the car wouldn't move any more. At this point the car stayed in D, until I opened the door then it went automatically into park and set the park brake. I was able to select N to push it into a spot. Called up my bother and he came and got me. I went home and got my 2003 Suzuki and brought it back. Experiment time. I have a 2000Watt inverter powered by 2 deep cycle batteries in my Suzuki and thought I could hook up the 110V charge cord to get a little charge into the Bolt. However the EVSE charger didn't detect a good ground off the Suzuki and wouldn't charge. I'll fix that later. So I decided that putting the Bolt in N and just pulling it home was my best bet. Had the wife with me so she drove the Suzuki and I steered the Bolt. We went no more than 20MPH the 4 miles to home. Plugged in and charged up for the next morning. However, the next morning I had the Service Vehicle Light on. Checked the codes and they were P0AC4, P0C11, P0C12, P0C13. Car drove fine for 25 miles to my destination where I shut the car off. After restarting from there to get me home the light was off and did not return on a couple other trips. I took to the dealership and explained what I had done. They didn't know as nothing like this has ever happened before. I have a theory that because the drive motor had no power to it while it was being towed in neutral that it detected the motion with the drive motor not functioning and threw the codes. Chevy checked over the car, cleared the codes, test drove it and sent me on my way with an $80 bill. I theorize that if I do this again I intend to have a good ground so my Suzuki can charge the bolt long enough to get the drive motor active and back in D, then I will hook it up and tow it with the Suzuki so it will recharge the batteries again while being towed and there will be no problem, or just call roadside assistance. Questions: I'll try. I'm pretty good at testing things like this in situations like this.

 

[TotaledJetta]

Nice work on the experiment. I think I will try to avoid replicating that. Not sure towing it in drive to charge it would be a good idea, but let us know if you try it. :nerd:

I can tell you what happens when a Bolt runs out of juice. I ran mine out just 4 miles from my house. It seems that when it gets to the low point and you can no longer see how many miles are left, that there is about 6 miles left before out. I was able to be doing 50MPH when it started going empty, the power meter showing drain will get less and less despite putting the accelerator pedal to the floor and my speed was gradually decreasing. I was able to go about 1/4 to 1/2 mile with the foot to the floor before finding a parking lot to settle in. The gauge showed 0 miles left and the car wouldn't move any more. At this point the car stayed in D, until I opened the door then it went automatically into park and set the park brake. I was able to select N to push it into a spot. Called up my bother and he came and got me. I went home and got my 2003 Suzuki and brought it back. Experiment time. I have a 2000Watt inverter powered by 2 deep cycle batteries in my Suzuki and thought I could hook up the 110V charge cord to get a little charge into the Bolt. However the EVSE charger didn't detect a good ground off the Suzuki and wouldn't charge. I'll fix that later. So I decided that putting the Bolt in N and just pulling it home was my best bet. Had the wife with me so she drove the Suzuki and I steered the Bolt. We went no more than 20MPH the 4 miles to home. Plugged in and charged up for the next morning. However, the next morning I had the Service Vehicle Light on. Checked the codes and they were P0AC4, P0C11, P0C12, P0C13. Car drove fine for 25 miles to my destination where I shut the car off. After restarting from there to get me home the light was off and did not return on a couple other trips. I took to the dealership and explained what I had done. They didn't know as nothing like this has ever happened before. I have a theory that because the drive motor had no power to it while it was being towed in neutral that it detected the motion with the drive motor not functioning and threw the codes. Chevy checked over the car, cleared the codes, test drove it and sent me on my way with an $80 bill. I theorize that if I do this again I intend to have a good ground so my Suzuki can charge the bolt long enough to get the drive motor active and back in D, then I will hook it up and tow it with the Suzuki so it will recharge the batteries again while being towed and there will be no problem, or just call roadside assistance. Questions: I'll try. I'm pretty good at testing things like this in situations like this.

 

[GJETSON]

We went no more than 20 MPH the 4 miles to home. .

Just so you know, the ATF circulating pump does not run when the Bolt is in Neutral. I don't know how far, or how fast you would need to go to ruin the bearings, and gall the gear teeth, but I wouldn't want to find out.

 

[madmike]

Yikes and glad you made it.

 

[GJETSON]

Not sure towing it in drive to charge it would be a good idea, but let us know if you try it. :nerd:

It has been done with other EVs. I don't see a problem, other than it being very inefficient.

 

[surgeonFWW]

It has been done with other EVs. I don't see a problem, other than it being very inefficient.

I agree. Should it not be similar to a long downhill coast?

 

[ibboltin]

Almost seems like we need a switch to put it in reduced power mode, and extend the range

OK I am just speculating here, but I am pretty sure the power reduced is a protection mechanism for the cells. Matting the pedal would typically draw a huge amount of current but at this point the batteries are almost depleted. Lition Ion batteries dont fare well when the voltage falls below 3.0 volts typically. And you can see in the attached discharge curve that it falls fast when almost depleted. DOnt want to go into a long technical discussion but suffice it to say battery voltage varies with current draw. High current draws will reduce the voltage but as soon as the current is removed the voltage will go back up (recover).

https://learn.adafruit.com/li-ion-and-lipoly-batteries/voltages

So its a safety for the cells.