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Discussion Starter · #1 ·
The 2017-2018 Bolt has only two charge settings, 100% or hilltop reserve which is 88%.

But you can "target charge" to a lower level if you want by using departure charging and have it believe that your departure is later than you actually will depart.

For example, if you have 7 kW charging, set hilltop reserve, and set your departure time to a hour after when you will actually depart, then you will depart with approximately 76% charge level.
 

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I do this every day. 7am departure setting, leave at 4:20am. About 60 percent charged. This leaves me with about 40 miles range when I get to work, so i can use free charger a full 8 hours.
80mi one way commute.
 

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Worth noting here that if you’re dealing with peak/off-peak rates this gets more complicated. My rates go from $0.0765/kWh to $0.53/kWh at 7am so the Bolt stops charging then because… you know… utility price gouging ugh. Anyways… that messes with my 8:30am departure time. Now I just run the Bolt down to nominal voltage around 55% and just 12a trickle it overnight, which gets me back up to almost 80%, which is perfect for my daily needs.

But yeah… unnecessarily complicated.
 

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This brings up a sore spot for me in terms of GM’s administration of the recall. If an 80% charge is safer than a 90% charge (and I don’t know for a fact that it is), why wouldn’t GM open up Target Charging to 2017-2018 models? Why force us to try and do this manually?

I was hoping that the April software update would have done so as a gesture of goodwill. Ok, GM prefers to make users upgrade for newer features, I get that.

But now it seems we’re in different territory. If GM is going to ask us to live with these limitations to keep us safe, and if we might feel safer with an 80% charge, GM should offer us more tools than Hilltop Reserve.
 

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This brings up a sore spot for me in terms of GM’s administration of the recall. If an 80% charge is safer than a 90% charge (and I don’t know for a fact that it is), why wouldn’t GM open up Target Charging to 2017-2018 models? Why force us to try and do this manually?

I was hoping that the April software update would have done so as a gesture of goodwill. Ok, GM prefers to make users upgrade for newer features, I get that.

But now it seems we’re in different territory. If GM is going to ask us to live with these limitations to keep us safe, and if we might feel safer with an 80% charge, GM should offer us more tools than Hilltop Reserve.
I did not have the temporary fix done last fall once I found out that it took away HTR and left you with 95% vs being able to select 88% or 100%. If we didn’t get it with either software fix, I don’t think there is any chance we get it now.
 

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Getting a target charge update on early Bolts has been on our wishlist for years. I think someone even started a petition. No such luck. Chevy will not budge.
 

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Getting a target charge update on early Bolts has been on our wishlist for years. I think someone even started a petition. No such luck. Chevy will not budge.
Has any hacker type tried pulling a binary image of an early 2019 (with the Korean battery) computer with target charge and installing it in a 2017 or 18? Did they brick the car?
 

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Has any hacker type tried pulling a binary image of an early 2019 (with the Korean battery) computer with target charge and installing it in a 2017 or 18? Did they brick the car?
This has me thinking… how hard would it be to create a little Bluetooth hardware device that connects to OBD & connects physically to the J1772 control pin… somehow like an adapter type thingy… and when DIC PID hits a predetermined percentage just flips the CP back up to 9 volt Status B state tricking the EVSE into stopping the charge. All other pins pass through or whatever. Just mimicking car signals to the EVSE. Though… the Bolt would still be requesting the charge so would think the EVSE failed or something. Hmm. I know nothing. I do know my ‘17 WANTS TARGET CHARGE! Haha.
 

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This has me thinking… how hard would it be to create a little Bluetooth hardware device that connects to OBD & connects physically to the J1772 control pin… somehow like an adapter type thingy… and when DIC PID hits a predetermined percentage just flips the CP back up to 9 volt Status B state tricking the EVSE into stopping the charge. All other pins pass through or whatever. Just mimicking car signals to the EVSE. Though… the Bolt would still be requesting the charge so would think the EVSE failed or something. Hmm. I know nothing. I do know my ‘17 WANTS TARGET CHARGE! Haha.
Without putting too much thought into it, I would think easier than messing with the CP would be hacking a little relay into the proximity pilot, and have this hypothetical device open the circuit when you want to stop charging. That would simulate pressing the thumb button on the J1772 handle and the car would immediately stop charging.
 

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Without putting too much thought into it, I would think easier than messing with the CP would be hacking a little relay into the proximity pilot, and have this hypothetical device open the circuit when you want to stop charging. That would simulate pressing the thumb button on the J1772 handle and the car would immediately stop charging.
That’s a way better idea. Thanks. Even better idea is have GM just install target charge on earlier models haha. Sigh.
 

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2021 chevy bolt premier ev
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Getting a target charge update on early Bolts has been on our wishlist for years. I think someone even started a petition. No such luck. Chevy will not budge.
GM might give the 2017/19 bolts target charging when they put the 66 KWH batteries in all the earlier bolts
 

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GM might give the 2017/19 bolts target charging when they put the 66 KWH batteries in all the earlier bolts
If GM were going to give us 2017 owners target charge they would have done it with the software fix to further reduce fire risk (for those who want to charge to <88%). I think there is no chance we ever get it. My understanding is that the extra capacity from newer batteries is essentially accidental in the 2017-2018, in that the same target voltages correspond to more kWh (via new target voltages). Which could be a blessing…if GM were concerned that lack of buffer increased fire risk, they could give older owners newer batteries and then hard cap them to 60 kWh. They say they won’t do this, so I assume that means there will be no software update for target charge.
 

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If GM were going to give us 2017 owners target charge they would have done it with the software fix to further reduce fire risk (for those who want to charge to <88%). I think there is no chance we ever get it. My understanding is that the extra capacity from newer batteries is essentially accidental in the 2017-2018, in that the same target voltages correspond to more kWh (via new target voltages). Which could be a blessing…if GM were concerned that lack of buffer increased fire risk, they could give older owners newer batteries and then hard cap them to 60 kWh. They say they won’t do this, so I assume that means there will be no software update for target charge.
I'm sure that was before GM decided to put the latest battery and technology into the 2017/19 bolts
 

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I'm sure that was before GM decided to put the latest battery and technology into the 2017/19 bolts
My point is that they are only putting in the new battery modules, an not updating software.

If they were going to update the software the safest move would be to limit us to 60 kWh of usable battery and leave the rest as a buffer since we aren’t owed any more than that. The fact that we are getting an extra 6 kWh from that battery likely indicates that they are not updating anything other than the modules.
 

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Discussion Starter · #15 ·
The most recent software from the first fire recall final remedy is supposedly compatible with all old, all new, or mixed modules (although mixed modules will give a pack with capacity based on the old modules). So they would not have to do a new software update when they replace (now all) modules in 2017-2019 cars, since the existing software from the first fire recall final remedy is compatible with all new modules.
 

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This brings up a sore spot for me in terms of GM’s administration of the recall. If an 80% charge is safer than a 90% charge (and I don’t know for a fact that it is), why wouldn’t GM open up Target Charging to 2017-2018 models? Why force us to try and do this manually?
Because GM is so committed to the principle of never under any circumstances giving owners of existing vehicles new features they took additional time and spend money to develop a different version of the software "fix" for <2019 Bolts that did not include TCS.
 
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