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I have seen several posts on here where people claim they can recharge a little by running in mountain mode.. i have a 2012 and was driving down the freeway with no charge left so i drove in mountain mode for 5-10 min or so expecting to see some charge when I switched back to normal mode but this wasnt the case. is this something that doesnt happen anymore with the 2012's or was i doing something wrong or does this just not happen at all?:D:D
 

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I too have a 2012, and it will recharge but it probably will take more than 10 min or so. I've done it twice. After about 45 min of driving, I think I gained about 7 EV miles. I'm not sure if it makes sense efficiency wise, but it is kind of nice to get back to EV mode :)
 

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Mountain Mode--Observed behavior

I have been successful in using mountain mode both to maintain charge at ~35% as well as (i think ) to recharge the battery somewhat when its below that level--never from 0% however. My evidence that its working is that after several minutes, the energy bar has gone up one tic, and I have a point in my drive that I know I can turn off MM and make it home on battery alone, I make it versus if I had not used MM.

I have seen several posts on here where people claim they can recharge a little by running in mountain mode.. i have a 2012 and was driving down the freeway with no charge left so i drove in mountain mode for 5-10 min or so expecting to see some charge when I switched back to normal mode but this wasnt the case. is this something that doesnt happen anymore with the 2012's or was i doing something wrong or does this just not happen at all?:D:D
 

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Mountain mode is more effective when you have about 7 mile of range left on the battery. I believe that is the trigger point in order for the ICE to come on immediately. If you start out in mountain mode with a full charge the ICE will delay you will immediately see a decrease of EV range by about 7 miles. Mountain mode is also not friendly to your ICE mpg and is best used for its intended purpose which s to build charge for steep long grades. I believe this is why they instituted Hold mode in the 2013 models. this mode should allow maximizing ICE mpg while flexibly allowing for judicious use of you EV rande in high traffic and city driving situations.
 

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MM Always recharges the battery back up to 14-15 miles of range. (or stops it from dropping below that if engaged above that range)

The only weird thing is that if your range is below about 5 miles when engaging MM, it will not show the battery range when MM is disengaged, unless you shut off the car and restart it.
 

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Mountain mode is also not friendly to your ICE mpg and is best used for its intended purpose which s to build charge for steep long grades. I believe this is why they instituted Hold mode in the 2013 models. this mode should allow maximizing ICE mpg while flexibly allowing for judicious use of you EV rande in high traffic and city driving situations.
That statement isn't true, Mountain mode makes EV range that is not counted toward your fuel economy, I hope chevy fixes this bug so the real gas MPG shows
 

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From the Horses (GM's) mouth:
When the vehicle reaches the end of its electric range, it switches to Extended Range Mode. In this mode, electricity is produced by the drive motor, which is driven by the internal combustion engine (ICE). This secondary source of electric power extends the vehicle range. Operation will continue in extended range mode until the vehicle can be plugged in to recharge the hybrid/EV battery pack and restore electric mode.

The hybrid/EV battery pack will continue to provide some power and work together with the ICE to provide peak performance when it is required, such as driving up a steep incline or during high acceleration. The hybrid/EV battery pack will not be recharged while in extended range mode.
 

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And you might recoup energy here :When the vehicle is coasting or braking the power inverter module may operate the drive motor as a generator in an Electrical Generation Mode. Operating as an electrical generator, the drive motor exerts a driveline load that helps to slow the vehicle. The electrical energy that the drive motor creates is transferred by the power inverter module to the hybrid/EV battery pack. Constant communication between the power inverter module and the electronic brake control module allows the blending of regenerative braking force with hydraulic braking force.
From the Horses (GM's) mouth:
When the vehicle reaches the end of its electric range, it switches to Extended Range Mode. In this mode, electricity is produced by the drive motor, which is driven by the internal combustion engine (ICE). This secondary source of electric power extends the vehicle range. Operation will continue in extended range mode until the vehicle can be plugged in to recharge the hybrid/EV battery pack and restore electric mode.



The hybrid/EV battery pack will continue to provide some power and work together with the ICE to provide peak performance when it is required, such as driving up a steep incline or during high acceleration. The hybrid/EV battery pack will not be recharged while in extended range mode.
 

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I paid a little attention to this during my 800 mile drive on gasoline. I set my Cruse Control at 65mpg, and I watch the Energy screen with the tires and battery pack with the animation....

Driving back from FL to TX on I-10, the highway is hilly. In "normal mode", I notice that on the downslide for every couple of hills, the energy animation moves from the tires into the battery. Then, for about 10 seconds, the energy travels from the battery back to wheels for the car to maintain the cruise speed or to accelerate because it is climbing the next hill. This patterns seems to repeat....charge up the downslide of a few hills (5-10), build enough electricity to use it all up in 10 seconds. I never got to see the first bar ever light up green, until....

When I switched over "mountain mode", animation was basically the same, however, I never see it use any electricity. I am assume the incline on the hills were not severe enough that it needs to use more energy. After about 20-25 hills or so, I noticed the first bar of on the battery lit up to be green. When I switched over to "normal" mode, the battery was all used up within 1-2 minutes, and turned to be unlit.

From my observation, the gas engine tries to produce "just" enough electricity for me to drive / maintain my cruise speed of 65 mph. There is no animation that suggest that any energy is being transfered back to the battery. I suspect there is a little, but probably nothing worth noting in the animation compared to the regen braking. Therefore, the battery seems to be primarily charged with regen braking--I do not believe the gasoline generator tries to produce excess electricity to provide the current cruise control and battery storage. I also think the main difference between mountain and normal is that drive will try to use electricity when avilable while mountain will only do that if the reserve is more than 15 miles.

Also, I got about 41.5 mpg with the AC on ECO mode with mostly cruise control (no braking). Those are awesome mileages from a single gallon of gasoline, I cannot imagine that gasoline would be burned into excess electricity, then storing that electricity into the battery at a loss of 30%--if so, GM should have tuned the generator to give me 54 mpg (30% more) on gas alone to be used as "bragging rights".

I am assuming if the car charges like my 110V charger, it would take 1 hour of continuous charges to get the equivalent of 4 miles or 1 bar. I am not sure if the gas motor is as powerful as a 220V charger, but that same equivalence would take a full 30 minutes. Neither scenario is my preference because I believe charging the battery simply takes away from my 41.5mpg (gasoline) miles. Electricity from the plug is 10-20x cheaper than electricity from the gasoline engine. To me, it makes no sense to create inefficient surplus electricity and waste about 30% to convert it into battery storage.

I hope my observation can help in some ways.

-KyleH
 

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I too have a 2012, and it will recharge but it probably will take more than 10 min or so. I've done it twice. After about 45 min of driving, I think I gained about 7 EV miles. I'm not sure if it makes sense efficiency wise, but it is kind of nice to get back to EV mode :)
Using the gasoline engine to charge the battery (Any amount.) costs 4-10 times more money than plugging it in to charge.
 

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How I use Mountain Mode.

Out the garage I usually have 42-45 miles displaying on the battery. Once I hit the freeway I switch to Mountain Mode. My miles on my battery drop to 22-24. I go about 22-24 miles on pure battery then the car switches to gas. I do this assuming the gas engine is more efficient propelling the car when going over 65-70 miles.
Once I get off the freeway and back to city driving I switch from mountain mode to normal mode. My battery miles pop back up to around 13-17 miles. I do this assuming the battery is used more efficiently when in lower speeds. Also once I get to my destination I can plug in and get up to 25 miles in a couple hours and keep using the car in EV mode longer than if went in normal mode the whole way through the trip.

On mountain mode on the freeway I get about 37 - 40mpg. This is open road not traffic. If there is traffic i stick to EV and can get up to 45+ on EV alone.

Am i correct in my assumptions?
 

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MM Always recharges the battery back up to 14-15 miles of range. (or stops it from dropping below that if engaged above that range)

The only weird thing is that if your range is below about 5 miles when engaging MM, it will not show the battery range when MM is disengaged, unless you shut off the car and restart it.
+1

About the second sentence -- I don't know if this is exactly accurate or not, but there is definitely something quirky that can happen in limited cases. It might be when you _disengage_ MM with less than 5 miles, it doesn't revert to electric drive unless you shut the car off and turn it back on. Not sure.

Data Points:
I once engaged MM with no EV range, and it immediately switched back to EV drive when I disengaged MM; on that instance the EV range was 7 miles upon disengage of MM. Another time, same scenario, only when I disengaged MM the engine remained on and it didn't switch back to EV mode. I turned car off and back on, and it came back on in EV mode with 4 miles EV range showing.

MM can definitely recharge the battery at a high rate, assuming you are not heavily taxing the gas engine. The time I tried it in town at low speeds, it recharged to 7 miles estimated range (from nothing) in only 15 minutes. That's pretty fast.

MM is supposed to be set for 45% SOC. I know that when I engage it, estimated range drops about 14 miles, and when I turn it off after a long highway drive, it shows about 14 EV miles left.
 

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KyleH said:
When I switched over "mountain mode", animation was basically the same, however, I never see it use any electricity. I am assume the incline on the hills were not severe enough that it needs to use more energy. After about 20-25 hills or so, I noticed the first bar of on the battery lit up to be green. When I switched over to "normal" mode, the battery was all used up within 1-2 minutes, and turned to be unlit.
This is not how it's supposed to work. After 20-25 miles in MM, assuming you're not climbing up a mountain the whole time, the battery should be about 30% "full" although I don't recall how it looked on the battery gauge. You should get an easy 10-15 EV miles.


I am assuming if the car charges like my 110V charger, it would take 1 hour of continuous charges to get the equivalent of 4 miles or 1 bar. I am not sure if the gas motor is as powerful as a 220V charger, but that same equivalence would take a full 30 minutes. Neither scenario is my preference because I believe charging the battery simply takes away from my 41.5mpg (gasoline) miles. Electricity from the plug is 10-20x cheaper than electricity from the gasoline engine. To me, it makes no sense to create inefficient surplus electricity and waste about 30% to convert it into battery storage.
The car can charge MUCH faster than 110 or even 220 from the wall. Switching from Normal to MM when in CS (assuming driving on level ground) requires about 20 minutes to add 3kW/h to the pack IIRC. That takes nearly 3 hours from a 110 socket.

Believe it or not, it appears to be similarly (or possibly more) efficient to charge the battery with the engine (using the MM game), then drive EV until depleted compared to running normally in CS mode. The reason is that the engine runs very efficiently, with less concern for NVH, while doing so.
 

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I have seen several posts on here where people claim they can recharge a little by running in mountain mode.. i have a 2012 and was driving down the freeway with no charge left so i drove in mountain mode for 5-10 min or so expecting to see some charge when I switched back to normal mode but this wasnt the case. is this something that doesnt happen anymore with the 2012's or was i doing something wrong or does this just not happen at all?:D:D
Mountain mode doesn't put bars back up, even though it is charging the battery. I'm not 100% sure why GM made this decision - my guess is they did it to keep people who had no clue what was going on from thinking they were getting "free" power that way, and then reporting what awful gas mileage the car got.

If you'd looked at the power flow screen after you switched off mountain mode, you would have seen that even though it is still in CS and accruing "gas" miles, the car didn't turn the engine on for the next several miles while the battery drained.
 

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Data Points:
I once engaged MM with no EV range, and it immediately switched back to EV drive when I disengaged MM; on that instance the EV range was 7 miles upon disengage of MM. Another time, same scenario, only when I disengaged MM the engine remained on and it didn't switch back to EV mode. I turned car off and back on, and it came back on in EV mode with 4 miles EV range showing.
Had you run the engine before that trip? How soon after turning it on did you switch back out of MM? I'm assuming that you know the engine actually stayed on, and not just that it continued to record everything as gas miles... If the engine actually stayed on, it most likely was because the engine hadn't finished warming up yet. Once the engine starts, it won't shut off until it reaches normal operating temperatures (maybe a minute? not sure exactly how long it takes.)

Normally it won't switch back to "EV" when you disengage MM unless you switched in with a few EV miles remaining - but the car will still shut the engine off and drive as an EV until the battery is drained again.
 

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I really think MM is not that mysterious. Basically it simply moves the SOC set point from 0% to around 30%. That new set point reserves roughly 14 miles of battery, if you switch out of MM after it has reached set point.

The one quirky aspect of MM is the DISPLAY after switching out of MM. I think it might have been less confusing if GM did not decide to lock in the ICE icon under certain circumstances (engaging MM too late, with 0% SOC), and instead always reverted back to the battery icon. That icon-locking behavior is really confusing. In fact, I still wonder if it is a defect.

For me, I always get the battery icon back because on long trips I never let the SOC reach 0%. I always go to MM on the highway almost immediately, even though I have plenty of SOC. I'm extremely confident about MM, and never hesitate to engage it. MM is my default setting on long trips. (Just like "L" is the only forward gear that I ever use.).

Trust me, MM is every bit as efficient as Normal, and easily will deliver 40-45 mpg when it is operating at target SOC (30%). Of course below target SOC it eats gas like crazy, as it should to get back up to target. Above target SOC it uses no gas at all, as it should because the battery provides juice until SOC comes down to target.

Once you get past the display anomaly MM is not mysterious at all.
 

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I'm not in a scenario to use much of the MM. But, I am thinking you guys are trying MM the way I would for maximum use. If this is a routine drive, you guys may want to maximize the drive home to try to get the eMiles as close to 0 as possible--so you can get charged up at home at cheap electricity rates.

I am starting to make mental "marks" on exits numbers before my house to see when I should undo the MM in order to maximize my trips to make it down to 0 at home. However, I have 2 freeway options to my house, and no 2 weekends seems to take me along the same paths.

-KyleH

I have played similar games. sounds close to my experience as well.
 

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Cool to know. I have a trip out of town in a few months; I will be able to try this. (I do not think there will be a chance to charge at the hotel.) And, I would like to get as much eMiles stored up for the next day to make short stop-n-go errands. (Of course, I will be looking for a electricity plug in the parking garage.)

-KyleH

Believe it or not, it appears to be similarly (or possibly more) efficient to charge the battery with the engine (using the MM game), then drive EV until depleted compared to running normally in CS mode. The reason is that the engine runs very efficiently, with less concern for NVH, while doing so.
 

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I am starting to make mental "marks" on exits numbers before my house to see when I should undo the MM in order to maximize my trips to make it down to 0 at home. However, I have 2 freeway options to my house, and no 2 weekends seems to take me along the same paths.

-KyleH
With NAV engaged this aspect of MM games becomes easy. Just watch for the point when you have about 14 miles to go to your next charge (usually my office or home for me), and switch out of MM then. With good timing, your battery will exhaust just as you pull in the driveway.

No doubt, the Volt is one of the funnest cars that I've ever owned.
 
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