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2012 Switches to gas mode with Battery Charge remaining

19336 Views 52 Replies 22 Participants Last post by  hellsop
I have a 2012 Chevy volt with 140,000 miles. It has not had any issues until now. The car will switch to gas mode while there is still plenty of charge remaining in the battery (as much as 80%). The temperature is well above freezing. Stopping, shutting of the car off and restarting resolves the issue. I took it to the dealer. however, the computer was not writing any errors codes.

Any ideas what could be causing this?
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If the outside air temp is around 40 degrees, it is possible that the engine is running simply to keep the battery pack and electronics at the optimal temperature. I know my '13 volt will run the ICE at temps of 37 or 38 degrees while driving down the highway.

On a side note, I'm having a different issue with my '13 Volt, and don't know nearly enough about the car to troubleshoot. I DO know that after fully charging the car on 240, and plug in my OBD-II gauge before I leave for work, it shows the battery at 86-87%.
When I drive the car, using all the EV before the ICE kicks on, I have driven roughly 35-40 miles on EV, consumed ~11 kWh, yet my gauge shows the battery at 18-22%. Until this past September or October, I was easily able to drive 45-60 miles on EV, and the car never dropped below 33 miles of estimated range in the winter. Now, I can never get the estimated range above 35, and My question is why? I have another thread that I was trying to get help on, without much help, so any help there would be awesome ... but for now, I return you to this thread ... sorry for the near hi-jacking.
The waste heat from the ICE running is only used to heat the cabin. The lithium battery pack has a dedicated electric battery heater (~2kW.) There is no heater for any of the Volt's electronics as none is required. There is no heating provided for the 12V AGM battery. The battery coolant, engine coolant and electronics coolant are each on an independent liquid (Dex-Cool) cooling loop with no cross feed among the loops. Each cooling loop has its own section of the Volt's radiator. The Voltec transmission also has its own independent core within the Volt's radiator.
Ice also warms up the hv battery, if running
How exactly does the ICE warm the HV battery, when running, if the ICE and battery coolant loops are separate? The radiator stack places the battery loop core at the front of the radiator, followed by the electronics core (top) and the Voltec transmission cooling core (bottom), backed by the ICE coolant core. If the radiator was a PB&J sandwich it would be: bread / jelly over peanut butter / more bread. The two sliced of bread are not even next to each other.
I guess you are right.

Ice coolant only warms the cabin

But the same chiller cools both the cabin and the battery, but I think there is a heat exchanger involved somewhere, so the systems remain separated
Here is an article that provides information on the Volt's cooling/heating:
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