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My 2013 Volt is up to date for all recalls and battery balancing. I've been getting the propulsion reduced messages five times over the last two months. It only happens when the battery is exhausted and I've been driving on gas for a while. I'll shut up the motor off wait about a half hour and then the error message appears whenI restart. The first time it happened, I couldn't drive any faster than 30 mph for the first 10 minutes. Then the motor ran enough to recharge the battery and I drove home normally under gas power. Lately the message comes up and the gas motor runs like mad and the message usually goes away in about two minutes. So I took the car to my local Chevy dealer and they could find no error codes and said they could not reproduce the problem. So I took it to another Chevy dealer, and they could not find any error codes or reproduce the problem. They said they did some reprogramming and gave me a printout from GM which said that occasionally this error message happens but usually if the car has been subjected to extremes of weather or if the car is going up a mountain. I live in Florida so I don't encounter too many mountains. So old I guess I'll just have to wait until the car completely stops before GM and my local Chevy dealer will do something about the issue. I'm still getting about 37 MPC but I think that the big battery may be losing some of its charge. Coolant levels are good. I've got 67,000 miles on the odometer. Ideas?
 

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I get this on hot days when I've depleted the battery and parked unplugged for a while. In Florida, I'm not surprised you see it occasionally.

Here's why: If the car has depleted the battery and is sitting in the sun or just heat soaks, the battery needs to cool down. The car will run the A/C to cool the battery, but you already have a low battery. This means that to run that A/C, the battery will have to dig into the reserve charge. So, when you start up the car, the software looks at that and says, "yikes, this battery is below minimum state of charge" and then fires up the engine to get it back up to the regular minimum S.O.C. It also prevents you from using full power to give the engine a chance to charge up the battery. So that's why you get reduced propulsion and why the engine is screaming away. It just needs to get you back to a good state of charge. It's a little odd, but it's a good thing because your battery is protecting itself from the heat.
 

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Frustrating for sure when there are no codes, can't be reproduced.

See the related threads area at the bottom of the page.
 

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I get this on hot days when I've depleted the battery and parked unplugged for a while. In Florida, I'm not surprised you see it occasionally.

Here's why: If the car has depleted the battery and is sitting in the sun or just heat soaks, the battery needs to cool down. The car will run the A/C to cool the battery, but you already have a low battery. This means that to run that A/C, the battery will have to dig into the reserve charge. So, when you start up the car, the software looks at that and says, "yikes, this battery is below minimum state of charge" and then fires up the engine to get it back up to the regular minimum S.O.C. It also prevents you from using full power to give the engine a chance to charge up the battery. So that's why you get reduced propulsion and why the engine is screaming away. It just needs to get you back to a good state of charge. It's a little odd, but it's a good thing because your battery is protecting itself from the heat.
I would bet it's this as well. Charge your car and keep it charged and you shouldn't have these problems. The Volt isn't a hybrid like a Prius. It's an electric car with a backup generator to extend it's range. Keeping the car in a depleted battery state will prematurely wear the battery because you are using it in the extremes of it's battery charge. GM designed the battery to work in the middle ~65% of it's charge because this is where lithium batteries are happiest. They maintain a strong charge and have long, happy lives being used in this middle 65% range. Using them outside that range stresses them. Prolonged stressing leads to weaker charges and shortened lifespan.
 

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brentalan: Excellent explanation !! I'm in Arizona and will also get the PPR message under the same condition. Deplete the battery, switch to gas for a short time before reaching my destination. If I start the car again in a reasonably short time I will get the PPR message. No error codes because it is working AS DESIGNED. I would bet this is what johnny mars is experiencing as well. My 2011 has over 123,000 miles and still going strong.
 

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I think I'd be interested to see if the PPR messages stop happening if the people that get them at startup leave the car on until the ICE shuts off on its own every time they're low enough to run the ICE. And then for the remainder that still get them that end up having bad battery sections replaced.
 

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I have a 2012 Volt with 131,000 miles and about 20k miles ago began to get the same message. it didnt matter how hot or cold it was here in Michigan. About every 3 times I start the car after depleting the battery fully, shutting the car off, run into a store quickly, then restarting the car, I get this message. Luckily the message seems to go away after slow driving for about 1-2 minutes. I havent bother with the dealer for 2 reasons. One, afraid they couldnt duplicate the issue, and 2, Im thinking its time to get a 2019 volt.
 

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Here’s one way to look at PPR as an aging issue, not as a malfunction:

The Volt switches from Electric to Extended Range Mode when the battery state of charge drops to ~20%, just a tad above the bottom "hard floor" level of ~15%. A normally operating 2013 Volt, with its 16.5 kWh battery, thus has only ~0.825 kWh of power in this 5% buffer for the car to "borrow" when generator output is insufficient to meet needs. THIS BUFFER IS ALSO THE SOURCE OF POWER USED BY MGA TO RESTART THE ENGINE AFTER THE CAR HAS BEEN TURNED OFF WHILE DRIVING WITH A FULLY DEPLETED BATTERY.

When the Volt is in good working condition, in most cases this small buffer is sufficient, and one is only encouraged to increase this buffer to prevent Propulsion Power Reduced episodes by switching to Mountain Mode before heading into driving conditions that may produce higher power demands.

Your Volt’s 8 yr/100,000 mile battery warranty says this: "Depending on use, the battery may degrade as little as 10% to as much as 30% of capacity over the warranty period" (which seems to have been increased to 10% to 40% for the Gen 2 Volt and Bolt).

"Acceptable" degradation over time impacts not only your Volt’s ev range and kWh Used per charge, but also how much power is being maintained in the 5% fully depleted battery buffer. The borrowable Extended Range Mode buffer power in a 2013 Volt may thus be susceptible to a drop from 0.825 kWh to 0.7 kWh or even 0.6 kWh while remaining within acceptable warranty limits.

If your early model Gen 1 Volt’s battery has experienced even a modest amount of degradation over time, conditions under which a Propulsion Power Reduced episode may be triggered may be encountered more frequently because less "borrowable" power is being maintained in the Extended Range Mode battery buffer.

Also more likely is that when you turn your car off during a drive (to go to a store, etc.), if the engine is running at that moment, the battery is being recharged to replace some borrowed power, and the soc is still below the "switch to gas" ~20% state of charge. When you then return to the car and try to start it, the charge in the battery is too close to the "hard floor" level, resulting in a Propulsion Power Reduced episode.

As Hellsop suggests above, before you turn off your Volt, wait until the engine stops running, which would then indicate the buffer is back up to the appropriate soc level. If your battery is a bit degraded from old age, that "topping off before shutting off" might be enough to provide adequate starting power without triggering the PPR.

One could, I suppose, counteract any reduction in the Gen 1 Extended Range depleted battery buffer size whenever one is anticipating driving beyond battery range by switching to Mountain Mode before the remaining battery power drops to the ~4 bar level (switching to MM when you first start driving is easier than remembering to do it later). This method will maintain sufficient charge in the battery to avoid PPR episodes when the car is turned off, and then started again a short time later.

If the vehicle is switched into MM before the battery SOC has dropped below the MM-maintained buffer level, all gas used will be used to generate power to propel the car and there will be no extra gas burned to recharge the battery. Then, when you are confident the car will be recharged before it is next turned off and then restarted, the car can be switched back from MM to Normal, and those ~4 bars of power (~14 ev miles) can be used during the final legs of the trip.
 

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Here’s one way to look at PPR as an aging issue, not as a malfunction:

The Volt switches from Electric to Extended Range Mode when the battery state of charge drops to ~20%, just a tad above the bottom "hard floor" level of ~15%. A normally operating 2013 Volt, with its 16.5 kWh battery, thus has only ~0.825 kWh of power in this 5% buffer for the car to "borrow" when generator output is insufficient to meet needs. THIS BUFFER IS ALSO THE SOURCE OF POWER USED BY MGA TO RESTART THE ENGINE AFTER THE CAR HAS BEEN TURNED OFF WHILE DRIVING WITH A FULLY DEPLETED BATTERY.

When the Volt is in good working condition, in most cases this small buffer is sufficient, and one is only encouraged to increase this buffer to prevent Propulsion Power Reduced episodes by switching to Mountain Mode before heading into driving conditions that may produce higher power demands.

Your Volt’s 8 yr/100,000 mile battery warranty says this: "Depending on use, the battery may degrade as little as 10% to as much as 30% of capacity over the warranty period" (which seems to have been increased to 10% to 40% for the Gen 2 Volt and Bolt).

"Acceptable" degradation over time impacts not only your Volt’s ev range and kWh Used per charge, but also how much power is being maintained in the 5% fully depleted battery buffer. The borrowable Extended Range Mode buffer power in a 2013 Volt may thus be susceptible to a drop from 0.825 kWh to 0.7 kWh or even 0.6 kWh while remaining within acceptable warranty limits.

If your early model Gen 1 Volt’s battery has experienced even a modest amount of degradation over time, conditions under which a Propulsion Power Reduced episode may be triggered may be encountered more frequently because less "borrowable" power is being maintained in the Extended Range Mode battery buffer.

Also more likely is that when you turn your car off during a drive (to go to a store, etc.), if the engine is running at that moment, the battery is being recharged to replace some borrowed power, and the soc is still below the "switch to gas" ~20% state of charge. When you then return to the car and try to start it, the charge in the battery is too close to the "hard floor" level, resulting in a Propulsion Power Reduced episode.

As Hellsop suggests above, before you turn off your Volt, wait until the engine stops running, which would then indicate the buffer is back up to the appropriate soc level. If your battery is a bit degraded from old age, that "topping off before shutting off" might be enough to provide adequate starting power without triggering the PPR.

One could, I suppose, counteract any reduction in the Gen 1 Extended Range depleted battery buffer size whenever one is anticipating driving beyond battery range by switching to Mountain Mode before the remaining battery power drops to the ~4 bar level (switching to MM when you first start driving is easier than remembering to do it later). This method will maintain sufficient charge in the battery to avoid PPR episodes when the car is turned off, and then started again a short time later.

If the vehicle is switched into MM before the battery SOC has dropped below the MM-maintained buffer level, all gas used will be used to generate power to propel the car and there will be no extra gas burned to recharge the battery. Then, when you are confident the car will be recharged before it is next turned off and then restarted, the car can be switched back from MM to Normal, and those ~4 bars of power (~14 ev miles) can be used during the final legs of the trip.
been trying this, so far so good. I wait a minute or so.
 

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been trying this, so far so good. I wait a minute or so.
Good to hear that "topping off before shutting off" might be enough to provide adequate starting power without triggering the PPR in an older Volt that’s lost some of its "oomph."

Another option for those who experience these PPR episodes when restarting an older Volt that had been running in Extended Range Mode before it was turned off is to add more to the battery buffer by switching to Mountain Mode just a couple of minutes before you reach that stop. This gives time for MM’s "recharging feature" to add a little more power to your "depleted battery buffer." When you then get back into your Volt and restart it, there’s enough available power to allow the car to be restarted without dropping the SOC far enough to provoke a PPR episode.

This method uses a little extra gas to do the recharging (perhaps a tenth of a gallon for those couple of minutes?), but if your battery is already depleted, this won’t add much to the trip’s total gas used.
 

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I get this on hot days when I've depleted the battery and parked unplugged for a while. In Florida, I'm not surprised you see it occasionally.

Here's why: If the car has depleted the battery and is sitting in the sun or just heat soaks, the battery needs to cool down. The car will run the A/C to cool the battery, but you already have a low battery. This means that to run that A/C, the battery will have to dig into the reserve charge. So, when you start up the car, the software looks at that and says, "yikes, this battery is below minimum state of charge" and then fires up the engine to get it back up to the regular minimum S.O.C. It also prevents you from using full power to give the engine a chance to charge up the battery. So that's why you get reduced propulsion and why the engine is screaming away. It just needs to get you back to a good state of charge. It's a little odd, but it's a good thing because your battery is protecting itself from the heat.
My ELR does this exact same thing.
 

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The propulsion message happened to me. Supposedly, it is a glitch that is corrected by a software update. (unless you have a real problem)
 
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