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Discussion Starter #1
For the past three days I can't regen the car with the button on back of steering wheel or downshifting from drive to "L", the car just coasts. There are no check engine or other lights on. My 17 Volt has 42000km on it. I wonder if one of the modules is reading too high a voltage because the hybrid buses I work on will disengage regen if one of the battery modules is too high. And no, this is not just happening when I just get into the car after unplugging it from the charger. It happens the whole drive. I drive 105km per day on a single charge and always use regen on the steering wheel/shifter to stop/slowdown.

thanks

Richard
 

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Can you contact OnStar from your location? Ask the OnStar representative if remote diagnostics report produces any error codes you can provide to the dealer.
 

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Please let us know what the dealer finds and fixes.
 

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Discussion Starter #4
Just tried to contact onstar. I can't connect because I cancelled my subscription and the recorded message only lets me contact GM Roadside Assistance. I just emailed Dan my Volt advisor and we'll see what he says. I'll bring it to the dealer on Wednesday and get back to you when I find out what's going on.
 

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Do your service brakes feel any different? If regen is out completely, when you apply them, they should feel abnormal to the way they usually feel to you.
 

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Discussion Starter #6
No problem with the brakes, they feel the same. If I'm just coasting to a stop in drive I'm getting -2 to -6 Kw back into the battery no matter what the speed. When trying the paddle regen today it felt like regen came on for a split second and then kicked out everytime i tried it including when I was shifting from drive to "L". I was also getting -2 to -6 kw back into the battery using the paddle. Depending on speed I've been able to get -59kw back into the battery, downhill with the paddle.
 

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Definitely keep us updated. Strange you would get any regen at all, even a little. I know when my Gen 1 had a bug and thought it was "overcharged" there was zero regen at all--car operated like it was in "neutral" when coasting.

It's also strange you brought this up as today I noticed my regen paddle went "out" for a second (then came right back). Since this never happened before I thought maybe I momentarily relaxed my grip, maybe tapped the go pedal unknowingly, or possibly the traction control tripped on for a moment. However, I'm going to be more aware of it now.
 

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Do you see additional regen over the normal -2 to -6 when applying the brakes? You should get a fair bit of regen before the physical brakes start to grab, similar to what you'd get with L or the regen paddle.
 

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I’m guessing it’s a brake sensor on the pedal. If you were doing a successful full regen, as soon as you press the brake pedal, the full regen disengages and regen is controlled by articulating the brake pedal. So if this sensor was always showing that you are riding the brakes, regen won’t engage.

One thing to try is pulling up on the brake pedal with your foot then attempt the regen paddle.

On the other hand, I don’t like driving in L nor do I believe the regen pedal actually helps your EV range. Variable regen afforded by the brakes usually achieves better range anyway.
 

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If your paddle kicked in for a second and then didn't, it sounds like the accelerator pedal is pressed down. Make sure there are no weather mats or anything pressing on the accelerator even a slight bit. If that still doesn't work, the throttle position sensor may need to be adjusted.

I believe in this case it will still regen during braking, and you'll see something close to -30 or -40 (or higher) kW on the power meter. If enabled, the green bar on the left will be down pretty far. If regen itself works, but just not from the paddle or "L", it's probably the accelerator pedal.
 

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Discussion Starter #11
I've noticed a few times while using the paddle to regen lately, it would kick out when going over a bumps in the road.
 

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I've noticed a few times while using the paddle to regen lately, it would kick out when going over a bumps in the road.
This is completely normal behavior.
 

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I've noticed a few times while using the paddle to regen lately, it would kick out when going over a bumps in the road.
That’s normal when traction control kicks in. The first few times it happens, it’s a bit disconcerting like unintended acceleration or brake failure. The fix is to not be slowing so fast (use the brake pedal instead, coast like the dickens instead of using heavy regen - you will see better overall EV range this way); if your tires are worn, get new tires; if you have really high mileage, maybe new shocks and struts are in order.

The reason for this behavior is in case you are in heavy regen and hit ice - you wouldn’t want to lose control and slide.
 

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The reason for this behavior is in case you are in heavy regen and hit ice - you wouldn’t want to lose control and slide.
It's more an unintentional side effect of how regen works, and because of this, any car with regen will suffer from it (Toyota used to be notorious for handling it very poorly, and wouldn't recover braking force with the friction brakes at all until the driver slammed the pedal down).

The max amount of braking you can get from regen ramps down as the speed decreases, so if the wheels start skidding from a bump (even just a tiny bit), there's a sudden loss in regen force and the vehicle gives up and switches to friction.
 

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The max amount of braking you can get from regen ramps down as the speed decreases, so if the wheels start skidding from a bump (even just a tiny bit), there's a sudden loss in regen force and the vehicle gives up and switches to friction.
Friction/regen, when you hit a bump you have no ability to brake/slow at all until the wheels reconnect with the ground.
 

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I’m guessing it’s a brake sensor on the pedal. If you were doing a successful full regen, as soon as you press the brake pedal, the full regen disengages and regen is controlled by articulating the brake pedal. So if this sensor was always showing that you are riding the brakes, regen won’t engage..
Good thought. If it's this, then cruise control probably won't engage either, and that's an EASY cross-check to do.
 

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It's more an unintentional side effect of how regen works, and because of this, any car with regen will suffer from it (Toyota used to be notorious for handling it very poorly, and wouldn't recover braking force with the friction brakes at all until the driver slammed the pedal down).

The max amount of braking you can get from regen ramps down as the speed decreases, so if the wheels start skidding from a bump (even just a tiny bit), there's a sudden loss in regen force and the vehicle gives up and switches to friction.
Although when I was testing my G1 during snowageddon 1 with ice on top of packed snow, in that instance I found that releasing the accelerator in L worked better than any amount of tapping on the brakes which would cause the ABS (that I affectionately call anti-brake locks) to engage and cause me to keep going and not stop. No matter how hard I tried, I could not get the front tires to break loose in a hard L regen. I'm guessing if I had regen paddles, it might, but without a G2 and effectively no Snowageddons the last 2 years, someone else either in Canada or Alaska would have to perform this experiment.
 

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I’m guessing it’s a brake sensor on the pedal. If you were doing a successful full regen, as soon as you press the brake pedal, the full regen disengages and regen is controlled by articulating the brake pedal. So if this sensor was always showing that you are riding the brakes, regen won’t engage.

One thing to try is pulling up on the brake pedal with your foot then attempt the regen paddle.

On the other hand, I don’t like driving in L nor do I believe the regen pedal actually helps your EV range. Variable regen afforded by the brakes usually achieves better range anyway.
Good thought. If it's this, then cruise control probably won't engage either, and that's an EASY cross-check to do.
That's not how my 16 works. If I'm holding the paddle down and press lightly on the brake pedal, it adds to the total braking force. It doesn't release the regen from the paddle at all. And if I take my foot off the brake again, it still remains full regen and I keep slowing down. So, if the brake pedal sensor were stuck like some of the ACC Volts were suffering from, it would be the opposite problem that the OP is having.
 

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That's not how my 16 works. If I'm holding the paddle down and press lightly on the brake pedal, it adds to the total braking force. It doesn't release the regen from the paddle at all. And if I take my foot off the brake again, it still remains full regen and I keep slowing down. So, if the brake pedal sensor were stuck like some of the ACC Volts were suffering from, it would be the opposite problem that the OP is having.
What happens if you tap the accelerator with the regen paddle pulled? Does that support your accelerator sensor theory?

I wonder if when pulling full regen and you hit the brakes, whether it's all friction braking or does regen go even higher with no friction brakes until the last few feet when it has to? The point is mostly academic for me as I don't have a regen paddle.
 

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That's not how my 16 works. If I'm holding the paddle down and press lightly on the brake pedal, it adds to the total braking force. It doesn't release the regen from the paddle at all. And if I take my foot off the brake again, it still remains full regen and I keep slowing down. So, if the brake pedal sensor were stuck like some of the ACC Volts were suffering from, it would be the opposite problem that the OP is having.
Same thing on the 17. The brake pedal adds a lot of force to the regen paddle. So much so that it's likely not just more regen, but actual friction braking.
 
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