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My otherwise flawless 2011 with 105,000 miles has exhibited this situation twice now. Normal cold weather battery range of 30-33 miles. The drive uses up the battery range, the engine comes on as normal but there's only 2-3 miles left in the trip so it runs at low rpm. I park outside in the 35 degree weather for an hour. Back in the car start it up and immediately have the "Reduced Propulsion " message with no check engine light. Start driving the engine revs up to what must be max rpm for about 2-3 minutes and of course acceleration is sluggish. After this high rev period the message goes away and normal ICE operation resumes. Yes I see another post describing this scenario with one case with a Volt still in warranty getting a battery replacement on GM. Are we seeing normal to be expected slight degradation of the battery which is triggering the programmed action? In other words normal per system expectations? My workaround may be to engage mountain mode 3-4 miles from destination to bump up state of charge. Or is the battery degradation which seems minimal a concern or cause?
 

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My otherwise flawless 2011 with 105,000 miles has exhibited this situation twice now. Normal cold weather battery range of 30-33 miles. The drive uses up the battery range, the engine comes on as normal but there's only 2-3 miles left in the trip so it runs at low rpm. I park outside in the 35 degree weather for an hour. Back in the car start it up and immediately have the "Reduced Propulsion " message with no check engine light. Start driving the engine revs up to what must be max rpm for about 2-3 minutes and of course acceleration is sluggish. After this high rev period the message goes away and normal ICE operation resumes. Yes I see another post describing this scenario with one case with a Volt still in warranty getting a battery replacement on GM. Are we seeing normal to be expected slight degradation of the battery which is triggering the programmed action? In other words normal per system expectations? My workaround may be to engage mountain mode 3-4 miles from destination to bump up state of charge. Or is the battery degradation which seems minimal a concern or cause?
The Volt ICE doesn't provide much power right after starting, to provide time to bring the parts and fluids up to temperature first, and colder temps means that warm up time is a little longer. Once those revs start climbing is when power is actually being generated and the car is playing "catch up" with the amount of reserve power remaining in the battery that's been used since the change to Charge Sustain (ICE) operation. Most people don't see a message about this, but their driving pattern or especially terrain may be different from yours. For them it's just "display switches, ICE starts and thrums gently for 45 seconds plus or minus, engine spins up to a whine for a few minutes, then settles back to the thrumming again. For you, if that spun up time corresponds with a long hill, I'd expect to see a message.
 

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I bought this 2011 Volt new ( had 3,200 as a demo) and this situation is new. Nothing has changed in typical driving scenario. Just looking for other early Volt adopters experience. I expect some minimal battery degradation in 7 years of use. We know from design specifications that when the switch to ICE comes a buffer remains in the battery. In my case it seems like something sensing state of charge sees a critical low situation and reacts to that with this max rpm charge. It's happened only twice in the last couple months. Otherwise everything is flawless including a 1500 mile trip south.
 

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Sounds like maybe the initial warmup/catchup was not completed so you were already below "0".
If you come to a park and the engine is still running - let it continue to run until it stops. Then shut off the car.
See if that makes a difference.

It may be the same driving pattern, but the SOC calculations swing over time to slightly less accurate. If it thought there was more charge than there really was (even by 0.4%), once it recalculates when you park for an hour, you could be into the PPR range if it was borderline.
Alternatively, the buffer likely runs on % of the battery (i.e. always 15% hard minimum, not x kWh).
In theory, if you've experienced 5% capacity loss, that window is now 5% smaller and as the battery ages, even if used the exact same way, you come closer to hitting the hard minimum unless you let it do the catch up charge when engine first on.

If you have an OBD reader, you can confirm this - what is the SOC (raw) when you parked and as you start it back up?
 

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I expect some minimal battery degradation in 7 years of use.
The first few Volts were sold in December 2010. Was yours one of them? The last 4 numbers of the VIN would be low, like 0012 for the twelfth car for example. Mine was a May 2011 car #3320. Your number displays on the center stack.

I have not seen this issue. Of course mine is still a baby at only 6 years, 6 months. :)
 

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Discussion Starter #7
My Volt is #2760 a 2011 Viridian Joule leather interior, backup camera etc. It's always garaged in a partially Earth sheltered area never colder than 50 in winter or warmer than 70 in summer. Of course when we are out it's 90 plus in summer and 10 or colder at times in winter for extremes. And yes Im still on the original 12V battery and thinking I should do a preventative change of that this week.
 

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Wikipedia says the 2011/2012 Volt is programmed to operate within a state of charge (SOC) window of 65% to maximize the life of the battery pack. For the 2012 Volt I’ve been driving now for 5.5+ years, that is approximately from 85-87% (raw SOC, fully charged) to 20-22% (fully depleted).

That also translates into a quantity of kWh Used per full charge for most of us, but the 2011 Volt has no kWh Used display on the energy usage screen.

My understanding is that when the Gen 1 Volt battery is fully depleted, the engine is clutched to the smaller motor to generate the electricity used as propulsion fuel by the primary motor. At times, the amount of power needed by the motor to maintain performance exceeds the generator’s output, and so the motor borrows some from the battery, and repays it when demand lessens.

When the battery is fully depleted, there’s not much borrowable power between the ~20% minimum SOC and the 15% hard limit. If performance demands seek more than that, there won’t be enough available to be "loaned," and the Volt enters Reduced Propulsion conditions. When power demand lessens, normal operations may return.

It would appear that as you reach your destination, your battery is fully depleted and you’ve been running the ICE for only a few miles. In the current Vicksburg weather environment (my sister lives in Portage, so I try to be aware of her weather, not sure if cold weather hit there earlier this year than last year to create conditions for this problem earlier), it’s rather cold and you likely haven’t been running the motor long enough to warm it up properly before turning it off at the destination, so it’s possible a bit of battery power has been "borrowed" and the SOC as you turn off the car is below the ~20% level... and then the battery management system might use a bit of power to maintain the battery as it’s sitting outdoors in 35 degree weather...

When you then start it up, the cold motor needs time to warm up, the SOC is now not far above the 15% bottom hard line limit, so the car determines you need to operate in Reduced Propulsion Mode until the motor warms up and can then generate a surplus to recharge the battery back to the ~20-22% normal minimum.

If this is what is happening, consider doing this:

Switch into Mountain Mode when you first start driving. In a 2011/2012 Volt, the ev range estimate will then immediately drop by ~14 ev miles (the MM-maintained buffer. Later models just gray out the bottom battery bars). The car will continue to operate in Electric Mode until the revised ev range drops to 0, and then it transitions to Extended Range Mode.

That won’t burn any "extra" gas to rebuild the battery buffer. Switching to MM with lots of grid power in the battery just temporarily increases the lower limit from ~20% to ~45% (according to Wikipedia). You’ll switch to gas ~14 miles sooner on your way to work, but then the motor will have time to warm up, and the SOC will be around ~45% when you park the car. That should be more than enough to help conduct battery maintenance while your 2011 Volt sits outside in the cold weather.

When you then return to your Volt and turn it on, most of that buffer you held on to by switching to MM as you started driving to work is now available. When you start the car, the battery icon should have some green bars, and when they are used, you will then transition as usual into Extended Range Mode, with the ICE starting up and taking you the rest of the way home, as it did taking you the rest of the way to work, with no Reduced Propulsion episodes.

Regarding the possibility of overall battery degradation (as distinct from problems with individual cells or groups of cells), my 2012 Chevrolet Limited Warranty and Owner Assistance Information manual says this about the 8 yr/100,000 mile battery warranty: "Depending on use, the battery may degrade as little as 10% to as much as 30% of capacity over the warranty period."

IOW, if your 2011/2012 Volt’s 16 kWh battery has somehow degraded 10% or even 30% within the first 8 years/100,000 miles it might still be within warranty specs. The window sticker rated these models at 35 ev miles. A degraded battery might take you only 31.5 ev miles (10%) or 24.5 ev miles (30%) and still be within warranty specs if the loss in ev range arose from battery degradation. Have you noticed any drop in your all-electric range over the years (seasonally adjusted, of course)?

Those OBD2 readers showing the SOC numbers can also show the kWh Used during a trip. Math says that dividing the kWh Used during a trip by the drop in raw SOC% will give an approximation (because the displayed numbers are "rounded off") of the current full battery capacity (start with a full charge and drive until the battery is depleted - the smaller the drop in SOC during the drive, the less precise the result).

The quantity of "borrowable" power in that "slice" between the 15% hard line and the 20% normal minimum SOC level in a degraded battery is, of course, even smaller than the quantity in a fully functional battery, producing Reduced Propulsion conditions more often. Perhaps that’s contributing to your recent experience, a little of your battery’s full capacity is starting to dribble off into the ether... if the engine keeps running as you reach the destination and stop, if you have time, let it run until it stops by itself (indicating the SOC is now back at the normal minimum level). Perhaps now it won’t enter Reduced Propulsion mode when you start it up again.
 

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In my opinion, that would be "normal". I know the OP says this is new to him, but it totally makes sense what it is doing. I am an Arizona owner and mine will sometimes do that during the summer. If you deplete the battery range very shortly before you reach your destination, you will get the reduced propulsion message next startup. Also, mine is a 2011 "3385" and see nearly zero battery degradation. Still getting mid 30 range, more during nice weather.
 
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My otherwise flawless 2011 with 105,000 miles has exhibited this situation twice now. Normal cold weather battery range of 30-33 miles. The drive uses up the battery range, the engine comes on as normal but there's only 2-3 miles left in the trip so it runs at low rpm. I park outside in the 35 degree weather for an hour. Back in the car start it up and immediately have the "Reduced Propulsion " message with no check engine light. Start driving the engine revs up to what must be max rpm for about 2-3 minutes and of course acceleration is sluggish. After this high rev period the message goes away and normal ICE operation resumes. Yes I see another post describing this scenario with one case with a Volt still in warranty getting a battery replacement on GM. Are we seeing normal to be expected slight degradation of the battery which is triggering the programmed action? In other words normal per system expectations? My workaround may be to engage mountain mode 3-4 miles from destination to bump up state of charge. Or is the battery degradation which seems minimal a concern or cause?
Hi caronjeff! One of my contacts touched base with me about your post and provided me some more information on your concerns. Per the information he sent me, there is a service calibration release that is available for certain 2011 and 2012 Volts. If you'd like to send me your VIN, current mileage, contact information and preferred dealership name via email to [email protected], I can reach out to your dealership to help get an appointment set up for you. At that appointment, your dealership can perform the necessary software flash and advise on the involved service costs.

Best,

Amber G.
Chevrolet Customer Care

To review our privacy policy, please visit https://www.gm.com/privacy-statement.html.
 

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I have an early 2011 Volt as well and I am experiencing the same issue as you. That is I get the "reduced propulsion mode" after depleting the battery, parking for a few minutes and then restarting the car. This is definitely not "normal". I had the car in for an oil change a few months ago with the dealer and complained about this problem. They ran some test, said everything was normal and simply handed me some sort of GM statement that this was normal operation and that I should use mountain mode. In my area we have few hills and I have never had to use mountain mode before. I am just barely under warranty for the drive train/battery as I have 79K currently. This seems like a rather large flaw and I hope there is a fix. I wouldn't be surprised if we all started to experience this (at least the early Volts).
 

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My otherwise flawless 2011 with 105,000 miles has exhibited this situation twice now. Normal cold weather battery range of 30-33 miles. The drive uses up the battery range, the engine comes on as normal but there's only 2-3 miles left in the trip so it runs at low rpm. I park outside in the 35 degree weather for an hour. Back in the car start it up and immediately have the "Reduced Propulsion " message with no check engine light. Start driving the engine revs up to what must be max rpm for about 2-3 minutes and of course acceleration is sluggish. After this high rev period the message goes away and normal ICE operation resumes. Yes I see another post describing this scenario with one case with a Volt still in warranty getting a battery replacement on GM. Are we seeing normal to be expected slight degradation of the battery which is triggering the programmed action? In other words normal per system expectations? My workaround may be to engage mountain mode 3-4 miles from destination to bump up state of charge. Or is the battery degradation which seems minimal a concern or cause?
I shall preface by saying, my driving terrain is flat, and my outdoor temperatures are moderate in North Texas. This car has been a peach and we have never spent much money on it for repairs, other than general maintenance and tires. It has been a dream to drive. And I will be sad to see it go when my next vehicle purchase occurs in mid 2018.

My 2011 Volt with 63K miles is at the service center right now. I have had the RPP (REDUCED PROPULSION POWER) coming on for 6-8 months always after depleting battery, arriving on ICE and parking for an hour or so. Once back in the car I start up then get the RPP message and the engine is really working hard (wish I could see RPM's). I have actually gotten out on the road and realized the power is truly diminished and could only get up to about 30mph and the sound and sluggish feeling was scary as well as a hot smell from the ICE. I started just letting the car run for 4-5 minutes while parked and it would eventually clear, but the car still seemed to be running loud and the engine sluggish for several miles, like dragging an elephant.

I took it into the dealer a couple of times and they could not even detect that a code had been displayed. They wanted me to bring it in when the code was present, but that does not work out, since it clears in a few minutes and I am a few miles from the dealership. I have gotten into the habit of switching to mountain mode before the battery is depleted to complete my trip. That way when I get back into the car after being parked, there is still about 10 miles of battery power to begin my trip and it all works out fine. However, bottom line, I should not have to remember to do this every time I am driving more than 30 miles. I have the car in now because of a SERVICE HIGH VOLTAGE CHARGING SYSTEM code. They said that turned out to be a faulty in the coolant level isolation circuit wire. But the battery was near depleted when I dropped it off , so I told them how to recreate the RPP code. After a couple tries and some driving around, they were successful. So now we shall see what they come up with. My 3/36 warranty is obviously out, but the 8/100 warranty is still in effect. I am going to be unhappy if this results in a huge expense for repair, especially since I have had it in a couple of times and they could not detect the code. My dealership has always bee fair with me, so I will see what happens.
 

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I shall preface by saying, my driving terrain is flat, and my outdoor temperatures are moderate in North Texas. This car has been a peach and we have never spent any money on it for repairs, other than general maintenance and tires. It has been a dream to drive. My 2011 with 63K miles is at the service center right now. I have had the RPP (REDUCED PROPULSION POWER) coming on for 6-8 months always after depleting battery, arriving on ICE and parking for an hour or so. Once back in the car I start up then get the RPP message and the engine is really working hard (wish I could see RPM's). I have actually gotten out on the road and realized the power is truly diminished and could only get up to about 30mph and the sound and sluggish feeling was scary. I started just letting the car run for 4-5 minutes while parked and it would eventually clear, but the car still seemed to be running loud and the engine sluggish for several miles, like dragging an elephant.

I took it into the dealer a couple of times and they could not even detect that a code had been displayed. They wanted me to bring it in when the code was present, but that does not work out, since it clears in a few minutes and I am miles from the dealership. I have gotten into the habit of switching to mountain mode before the battery is depleted to complete my trip. Then when I get back into the car after being parked, there is still battery power to begin my trip and it all works out fine. Bottom line, I should not have to remember to do this every time I am driving more than 30 miles. I have the car in now because of a SERVICE HIGH VOLTAGE CHARGING SYSTEM code. They said that turned out to be a faulty wire. But the battery was depleted, so I told them how to recreate the RPP code. After a couple tries and some driving around, they were successful. So now we shall see what they come up with. My BTB warranty is obviously out, but the VOLTEC warranty is still in effect. I am going to be very upset if this results in a huge expense for repair, especially since I have had it in a few times and they could not detect the code. I don't have a good feeling.
Perhaps they should take note that the 2011 and 2012 model years had an update to reduce the frequency at which this will happen. All Volts can experience this, just not as frequent as the 11 and 12s were having it.
 
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