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I'm the owner of a 2012 Volt and I do not have access to the "Hold mode". After many readings in these forums, sorry if I missed the info, I understand that switching to Mountain mode at a certain time could recharge the battery by swiching to the fuel engine and later by switching back to a normal mode I could use this energy to drive on the battery in the city. My question is what is the minimum mileage left on the battery to switch to the engine mode when passing on Moutain Mode?
 

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I don't think I understand the question.

Mountain mode preserves about 3.5 kWh of battery to use as a reserve for hill climbing (10-14 miles, depending on how you're driving and the weather.) If entered below that point, it recharges the battery to there by running the engine faster and harder than it otherwise would. If entered above that point, the car proceeds electrically until it reaches that point and the engine turns on.

Did I answer your question? If not, could you try restating it again, please?
 

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Zero.

Mountain Mode changes the 'spot' where the engine turns on by about 12-14 miles. If there's less than 12-14 miles (including when you've already depleted the battery and the engine is running), the engine will immediately turn on and run hard to charge the battery up to that point, so when you turn off MM there's some miles left. Note this is (90% of the time) less efficient than just letting the car figure it out. The best thing to do is turn on MM before you get to that 12-14 mile point so the engine doesn't have to work hard making that buffer. When the rest of the battery is depleted (leaving that buffer), the engine turns on, then when you get into town turn off MM and you have some battery miles left.

Mike.
 

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If you engage Mountain Mode with more than 40% battery remaining, the Volt will continue to operate in Battery electric mode until you reach 40% charge, at which point the engine will kick in and the car will operate as if it had a fully depleted battery, but maintain the 40% state of charge.

If instead you engage Mountain Mode below 40% state of charge, the engine will come on and not only create electricity to drive the car, but also create additional electricity to charge the battery back up to 40%, where it will then resume just creating enough electricity to propel the car.

One other detail. If you engage mountain mode after you already used ALL your battery up, and had been on engine power, then if you eventually return to normal mode on your drive, you will get battery electric driving for the charge that the battery has accumulated (i.e. the engine will be off), but the car will still count these on the display as gas miles and not electric miles. This is correct to do, since the energy here was derived from gasoline to charge the battery.

If you engage mountain mode before fully depleting the battery, and eventually return to normal mode during your trip, then the car doesn't know for certain what energy came from gas versus the wall, so it will count any battery electric driving here as electric miles and not gas miles.

Well that was a mouthful! Hopefully this helps :) As others stated, in most scenarios it is usually best to just drive the car in Normal mode unless 1) you need mountain mode to go up steep terrain for many miles, or 2) you know for certain that you will re-engage normal mode before you end your trip, and still use all the electric miles before the end of the trip. If you don't use all the electric miles by the end of the trip (i.e. deplete the battery completely), you've effectively used more gasoline than if you had just left the car in Normal mode.
 

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Discussion Starter #5
If you engage Mountain Mode with more than 40% battery remaining, the Volt will continue to operate in Battery electric mode until you reach 40% charge, at which point the engine will kick in and the car will operate as if it had a fully depleted battery, but maintain the 40% state of charge.
For the first try, I used this method. When switching to MM, I calculate that I will have 21 km left on battery, setup my nav system, drive and switch back to Normal 21 km from destination. It gave me 23km and I was able to finish my trip in the city in electric mode.
Could be adjusted cause I still had 5km available at arrival but the gas used on highway was the same as previous trip. So close to the Hold mode :)
 

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In passing, in addition to MM, the Volt will run the generator if the hood latch is released. Generally it is time limited.
 

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In passing, in addition to MM, the Volt will run the generator if the hood latch is released. Generally it is time limited.

Curiosity question:

When the latch hood is released and the gas engine runs is:
(a) the battery actually getting "charged" (just like in CS mode) or
(b) is it more like a "neutral" state where the gas engine is running (for a mechanic to work on it) but it is not actually charging the battery?

Perhaps I'm asking if clutch 'C3' is disengaged between the generator and the gas engine when running in the "hood activated" mode?
 

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Amp,

As I have read, when you open the hood the engine runs, but it is not generating any current. It's essentially idling.
 

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Amp,

As I have read, when you open the hood the engine runs, but it is not generating any current. It's essentially idling.
That's what the owners manual says - but according to the trials we've run with instrumented cars, the manual lies. When the engine is running because the hood is open and the battery is below the maximum state of charge, the car will charge the battery with power from the engine. I don't believe we've tested to see what happens if the hood is opened on a full battery.
 

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That's what the owners manual says - but according to the trials we've run with instrumented cars, the manual lies. When the engine is running because the hood is open and the battery is below the maximum state of charge, the car will charge the battery with power from the engine. I don't believe we've tested to see what happens if the hood is opened on a full battery.
What if, and I say, what if, one were to trick 2011 or 2012 Volt in thinking the hood is open by grounding or opening the switch that senses the hood being open. Could we then drive with the engine running? What I'm suggesting is this would be a "manual" hold mode for older Volts. Think this is possible?
 

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I plan to go on vacation in Nova Scotia to ride the Cape Breton. This scenic road is couple miles long with good road gradient I think 14% on 6 to 10 KM.

How I should expect the volt to behave?






 

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What if, and I say, what if, one were to trick 2011 or 2012 Volt in thinking the hood is open by grounding or opening the switch that senses the hood being open. Could we then drive with the engine running? What I'm suggesting is this would be a "manual" hold mode for older Volts. Think this is possible?
Not exactly. Search is your friend...

http://gm-volt.com/forum/showthread.php?31873-The-Hood-Switch-Experiment

Aside from the first time someone tried it which we haven't been able to repeat, we got something that's opposite to normal CS mode - engine on at low speeds, off at higher speeds.
 

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Not exactly. Search is your friend...

http://gm-volt.com/forum/showthread.php?31873-The-Hood-Switch-Experiment

Aside from the first time someone tried it which we haven't been able to repeat, we got something that's opposite to normal CS mode - engine on at low speeds, off at higher speeds.
Thanks. I didn't find it on my own. I knew someone had to have tried it. I found the thread very helpful. I don't really need a hold mode. But I like to see this "workaround" turned into a feature for 2012'ers (and older). I'm sure the bright, creative and crafty people here will find a way a way to do this.
 
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