[JohnnyHo]

I have high confidence that I have the range showing on the center dash, but it's ~40 mi below what it should be! Is the Bolt underestimating... do I have bad battery cells... or??

Max range at full charge hasn't been above 212 miles for a while. I have been monitoring usage and the dash estimates low range ~200 miles, but the radio display tells me driving efficiency is 4.9 mi/kWh. Note: GM recall - I had the battery replaced 5 months ago.


Current data:
- Energy used 4.5 kWh, distance traveled 22.3 mi = 4.96 mi/kWh
- Bolt steering wheel displays Max 174, probable 148 mi.

4.96 mi/kWh efficiency should have a probable & max range MUCH higher.


Any idea what's going on? Does anyone’s numbers match?

 

[redpoint5]

What battery was replaced (traction or 12v)?

How fast do you drive? I don't have a Bolt, but I would expect 5 miles per kWh to be something like 60 MPH.

 

[The Other Tom]

Hmmm...do you have hill top reserve set? Or if you car is a 2019 do you have it set to charge to 100%?
The Bolt has a 60kWh battery. At 4.5 mi/kWh, that should be 270 miles for a 100% charge. But if hill top reserve is set to 80%, then the GOM would show about 216 miles, which is pretty close to the 212 that you mentioned.

 

[Vertiformed]

Why does your efficiency history stop at 20 miles?

 

[JohnnyHo]

A. - Hill top reserve is off.
A. - Manual reset efficiency history at full charge to compare data.

I am driving efficiently and will drain the battery to get actual distance on full charge. Will do this 2-3x before I take it into Chevrolet Service.

From reddit for a Volt: GM sent me a letter claiming they want to monitor my battery health to ensure satisfaction, and I should activate OnStar Connected Access for free for two years so they can.


Are there any battery checks/software/tools that consumers can use?

 

[XJ12]

Are there any battery checks/software/tools that consumers can use?

you can try to use an On-Board Diagnostic II connector with an app on a cell phone. might be able to find if one cell is suspect, which is usually the case with a failing battery.

Here's a thread on the subject: https://www.chevybolt.org/forum/10-technical-discussion/26666-chevrolet-bolt-obd2-pids.html

 

[The Other Tom]

Did you see this thread?
https://www.chevybolt.org/forum/178...-range-keeps-dropping-dealer-second-time.html

 

[JohnnyHo]

Problem Identified - Low Voltage Cell #83

:|No error codes. No OnStar warnings. Just diminished range that I noticed. 170 mi range instead of 238. This seems to be/might be a standard decrement if a single cell fails. In a similar situation (attached below), one cell failed and the battery went from 60 kWh to 35 kWh which is very close to my calculated 38 kWh capacity. Note: Poster used a 3rd party tool to gather battery information.

Warning - my local dealer told me many times over 2 weeks that my battery was fine. I pressed for an answer why my range was low with high efficiency ~5 mi/kWh.. They kept saying driving habits vary, your battery is fully charged. You must force them to review the HV battery efficiency, kWh used and remaining battery life.

A very similar situation is detailed here..

 

[kendallg]

:|No error codes. No OnStar warnings. Just diminished range that I noticed. 170 mi range instead of 238. This seems to be/might be a standard decrement if a single cell fails. In a similar situation (attached below), one cell failed and the battery went from 60 kWh to 35 kWh which is very close to my calculated 38 kWh capacity. Note: Poster used a 3rd party tool to gather battery information.

Warning - my local dealer told me many times over 2 weeks that my battery was fine. I pressed for an answer why my range was low with high efficiency ~5 mi/kWh.. They kept saying driving habits vary, your battery is fully charged. You must force them to review the HV battery efficiency, kWh used and remaining battery life.

A very similar situation is detailed here..

Have you had them check the Hybrid Power Control module? I'm getting through a heck of a ride with my Bolt. It's now been in the shop for 3 weeks. On the original visit they did software updates and said it would solve a known issue. It didn't solve anything, my range was still ridiculously low. On the second visit they detected the HPCM 2 issue.

The part was backordered, took two weeks to receive. When they did receive it they couldn't get it to connect with the computer and had to open an official case with GM. I'm now waiting to hear back...

The symptoms you're seeing sound extremely similar to the ones I had/have...

My thread was this one: https://www.chevybolt.org/forum/178...-range-keeps-dropping-dealer-second-time.html

 

[JohnnyHo]

Battery Fix

Symptom: Decreased Capacity of High Voltage Battery (38 kWh usable of 60 kWh)
Initial Service Response: No DTCS found on any module. 51 mi test drive & vehicle working under specs
* I told them a test drive won't manifest the problem. Look at the energy consumed after any drive, compare kWh consumed with kWh remaining on battery and you will see it is not at full capacity. They contacted TAC (Chevrolet technical assistance?).
Problem Identified: #83 cell voltage out of specs (41% out of spec)
Resolution:Replace battery module (row 2).

The Bolt has 288 cells in the battery "pack" that are wired in series. One cell failure (3.71V [low] versus battery "pack" average of 4.14V), the entire battery runs at the reduced voltage. One bad cell reduced my 60 kWh battery to an effective 35 kWh.

If you experience low capacity, tell GM Service it is low "capacity". Capacity is the battery's energy, and range varies based on driving habits, temperatures, climate usage, etc."

Attached: GM's Hybrid/EV Battery Reduced Range Document ID: 5053779 diagnostic procedure and test results. EDIT: added individual pages.

 

[laurasheaclark]

Battery Fix

Symptom: Decreased Capacity of High Voltage Battery (38 kWh usable of 60 kWh)
Initial Service Response: No DTCS found on any module. 51 mi test drive & vehicle working under specs
* I told them a test drive won't manifest the problem. Look at the energy consumed after any drive, compare kWh consumed with kWh remaining on battery and you will see it is not at full capacity. They contacted TAC (Chevrolet technical assistance?).
Problem Identified: #83 cell voltage out of specs (41% out of spec)
Resolution:Replace battery module (row 2).

The Bolt has 288 cells in the battery "pack" that are wired in series. One cell failure (3.71V [low] versus battery "pack" average of 4.14V), the entire battery runs at the reduced voltage. One bad cell reduced my 60 kWh battery to an effective 35 kWh.

If you experience low capacity, tell GM Service it is low "capacity". Capacity is the battery's energy, and range varies based on driving habits, temperatures, climate usage, etc."

Attached: GM's Hybrid/EV Battery Reduced Range Document ID: 5053779 diagnostic procedure and test results. EDIT: added individual pages.

I have a 2017 Bolt EV, and one cell is consistently .3V lower than others, which are 4.1. The dealers that’s “normal,” but I don’t think so. I just escalated with GM Customer Care. How much difference does there need to be??