Downhill Extended Range Mode - Why? - Chevrolet Volt Forums: Chevy Volt Forum
 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 12-14-2013, 12:13 AM Thread Starter
Junior Member
 
Join Date: Dec 2013
Location: New Mexico
Posts: 2
Downhill Extended Range Mode - Why?

Hello everybody,
I own a 2013 Volt for one week now and I have noticed some indications on the energy status display which I can not explain.
I live on a mountain and on my daily commute to work it goes downhill for the first 9 miles. I leave home with a fully charged battery in Normal drive mode and the gas engine is off as you would expect. On the way down the hill I use LOW gear and the system is in REGEN most of the time. However - the MILE indication is that I am driving in Extended Range mode, with a full blue circle and increasing number of blue gas miles being driven. Electric miles driven stays at 0.0. At the same time the available EV miles increase from originally 41 to 60, which is maximum on the display. I fully understand this part because of the REGEN mode. The gas engine is definitely NOT running and the used gas indicator displays 0.00 gal during the whole trip. Today I switched from LOW to D after 12.2 miles and at that time the indication started showing EV miles being driven. At the end of the 22.2 Miles trip to work the indication showed 12.2 gas miles, 10.0 EV miles, total miles 22.2 and 0.00gal of gas used. The available EV range at my destination still showed 55miles, which is way optimistic but explainable with the energy use during the first 22 miles.
The MPG indicator showed 250+MPG the whole time.

On the way back home the system is in EV mode from the get go until about a mile before I reach home. Then the High Voltage battery is depleted and the Range extender comes on. The final indication was total 45 miles driven, 32 EV miles driven and 0.03 gal of gas used (for the last mile).

Does anybody has an explanation why the system shows Extended Range mode during the downhill with the gas engine being off?
Thanks
HighRollsVoltDriver is offline  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 12-14-2013, 03:34 AM
Member
 
TSquare's Avatar
 
Join Date: Mar 2012
Location: Nashville, TN
Posts: 35
It's sorta a bug in the software. What is happening is when you start off with a full battery and begin regeneration right away there is no room in the battery for the power from regen, so instead of just turning off the regen mode and making you use the friction brakes, the Volt activates the other motor, (the one that is attached to the engine), and lets the regen energy go against the generator motor. This way you still slow the car with regen but as you have noted it tricks the display into thinking you are using the engine without gas.

2013 Crystal Red, D-2516
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

U235 Powered
TSquare is offline  
post #3 of 4 (permalink) Old 12-14-2013, 08:28 PM Thread Starter
Junior Member
 
Join Date: Dec 2013
Location: New Mexico
Posts: 2
Tsquare, thanks for the information. This makes partially sense to me now.
The question still is, why the display switched to EV miles after 12 miles when I shifted from L to D and not as soon as Battery power was used for the first time after about 9 miles at the bottom of the hill.
BTW on the Onstar MYVOLT mileage chart the numbers appear correctly.There it says 22 EV-Miles and 0 Gas miles for that trip. Obviously the car reports different numbers to Onstar than it shows on its own display. Indeed there still seem to be some software queries.
HighRollsVoltDriver is offline  
 
post #4 of 4 (permalink) Old 12-14-2013, 11:12 PM
Member
 
TSquare's Avatar
 
Join Date: Mar 2012
Location: Nashville, TN
Posts: 35
Quote:
Originally Posted by HighRollsVoltDriver View Post
The question still is, why the display switched to EV miles after 12 miles when I shifted from L to D and not as soon as Battery power was used for the first time after about 9 miles at the bottom of the hill.
That one I'm not too sure about. However, I do know that the Volt is very good at keeping track of where the battery power came from originally, grid or generator. Since it thinks that the generator is running, (but not using gas), it would account for the power coming from the gas generator. Others have reported that when they are running on generator then go down a long hill that gets a lot of regen, their engine switches off, but their display continues counting the miles as gas powered.
BTW, if you haven't found it yet, come on over to gm-volt dot com. It is a much more active forum, lots of info and discussions.

2013 Crystal Red, D-2516
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

U235 Powered

Last edited by TSquare; 12-15-2013 at 02:44 AM.
TSquare is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevrolet Volt Forums: Chevy Volt Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome