[Riderice]

Hi all, just throwing this out there to share my recent scare with the dreaded "Propulsion power is reduced" message on 2017 Bolt. 28000 FLAWLESS miles, then one hot summer day (parked in garage, plugged into L2), I hit the remote start to pre-cool. 5mins later, turn ON to drive away and get the message (and service car symbol). Like I said, it had been PERFECT until then, so I was pretty startled. As I drove through my neighborhood it didn't seem weak, so I thought "maybe it was just a little hot from sitting in the garage, it'll probably go away once it cools off a little". But no, eventually I realized that power really was very much reduced and it wasn't really safe to drive. Parked it, then later that night (cooler temps), powered on and drove around just like normal - but the service car light still illuminated.

I used my OBD code reader and got a few codes, but little/no info anywhere. A few sounded like scary dead battery or main fuse problems. Anyway, the dealer took it in, "reprogrammed" something, and gave it back. It's been totally fine ever since (weeks of driving, all conditions and charge levels). I'll copy the service verbiage below, hopefully this helps someone in the future:

"Corrected by drive motor power inverter module reprogramming with SPS. Found DTC S P0AC4, P0AEE, P0BD2, P0BDC. Inspected and reprogrammed HPCM per TSB 18-NA-064 to correct. SPS code 17YN24133339."

Also wondering if anyone here can get their hands on that TSB, curious what it says...

 

[mooz]

With all that verbage they use I'm pretty sure all they did was reset the code.
What kind of temps were you charging at?

 

[GJETSON]

HPCM stands for hybrid ( or in the case of the Bolt more accurately high) power control module.

Issued 02/27/18

Technical Bulletin - #18-NA-064 - Malfunction Indicator Lamp (MIL) and/or Propulsion Power Reduced Message Displayed on Driver Information Center (DIC), DTCs P0AEE, P0BD2 or P0BDC Set - (Sep 17, 2021) - 2017 Chevrolet Bolt EV - Bolt EV Service Manual - RepairProcedures.com

Technical Bulletin - #18-NA-064 - Malfunction Indicator Lamp (MIL) and/or Propulsion Power Reduced Message Displayed on Driver Information Center (DIC), DTCs P0AEE, P0BD2 or P0BDC Set - (Sep 17, 2021) - For 2017 Chevrolet Bolt EV. This bulletin is found in the Bolt EV Service Manual. Service...

www.repairprocedures.com

2017 Chevy Bolt Problems and Top Complaints - Is Your Car A Lemon?

2017 Chevrolet Bolt is especially well known for having visibility, braking, propulsion and battery problems. Is your car a lemon? Lemberg Law can help you get Lemon Justice

www.lemberglaw.com

Hope this helps. Let us hope your problem is just the HPCM 2.

If you have Torque Pro, and Teleks PIDs, you can see the voltage of all 96 cells in the pack. It will be pretty obvious if you have a really low cell

 

[Riderice]

Hope this helps. Let us hope your problem is just the HPCM 2.

If you have Torque Pro, and Teleks PIDs, you can see the voltage of all 96 cells in the pack. It will be pretty obvious if you have a really low cell

That is helpful, thanks! I had been considering buying TorquePro (and bluetooth plug) to investigate my cell voltages... But I rarely get below 25% or even 50% charge so I don't know how obvious the problem will be yet, if there's a single cell dying somewhere in there...

I'm pretty sure all they did was reset the code.
What kind of temps were you charging at?

I'm not one to defend any dealership of taking credit (and/or money) for service they didn't provide, but in this case I'm sure they did reprogram the HPCM - either to mask a real problem, or to prevent false detects of a non-issue... The car had already been charged for many hours, but still plugged in sitting in a stuffy 115-120 degree garage, running the AC for a few minutes.

 

[GJETSON]

I found the highest, and lowest cells in our pack. I put gauges for them on either side of the pack average cell voltage gauge. I have checked the voltage spread for those two cells at everything from 100% DIC charge to 1.6% DIC charge. The spread typically ranges from 0.012 volts to 0.025 volts. The spread at 1.6% was 0.110 volts. So that low cell was in the knee in the voltage curve. If you have a bad cell in your pack, I would expect to see that kind of spread at higher states of charge.

 

[240vPlug]

I just had this happen today! Vehicle was charged and parked outside. It was going into conditioning mode (It was 95F outside) and plugged into L2. I didn't want to unplug while it was cooling the battery so I started the car while it was plugged in at which point the fan starting running very very loud. I heard the car give a series of beeps twice and when I got into the vehicle it said propulsion power reduced on the display. At first it seemed to drive normally but once I was driving for about 5 minutes I noticed that there was a significant delay when starting from stop. I also noticed a couple of instances where the regen didn't work or didn't work fully and I had to panic stop. I drove it about 30 miles and then parked it and pulled codes:

P0AEE
P0BD2
P0BDC
P0AC4

Cleared codes but I also received an email from OnStar stating that my Bolt has "An issue with the Engine and Transmission System " and to service it in 1 day. It has done some other random strange things in the past couple of months like not detecting the remote and refusing to charge. I noticed the TSB and I am really not looking forward to taking it into the dealer.

UPDATE: The issue has not returned. The vehicle is operating normally.

 

[GregBrew]

I just had this happen today! Vehicle was charged and parked outside. It was going into conditioning mode (It was 95F outside) and plugged into L2. I didn't want to unplug while it was cooling the battery so I started the car while it was plugged in at which point the fan starting running very very loud. I heard the car give a series of beeps twice and when I got into the vehicle it said propulsion power reduced on the display. At first it seemed to drive normally but once I was driving for about 5 minutes I noticed that there was a significant delay when starting from stop. I also noticed a couple of instances where the regen didn't work or didn't work fully and I had to panic stop. I drove it about 30 miles and then parked it and pulled codes:

P0AEE
P0BD2
P0BDC
P0AC4

Cleared codes but I also received an email from OnStar stating that my Bolt has "An issue with the Engine and Transmission System " and to service it in 1 day. It has done some other random strange things in the past couple of months like not detecting the remote and refusing to charge. I noticed the TSB and I am really not looking forward to taking it into the dealer.

UPDATE: The issue has not returned. The vehicle is operating normally.

I'd check the health of your 12V aux battery...

 

[240vPlug]

12v passes load test yesterday. I created a separate thread on the load test that I did. Read perfect all the way at the top of the green range and it dropped but remained in the green range under load for about 15 seconds. I went into the fuse panel for the first time and many of the fuses didn't seem to be seated all the way. Anyway I'm going to create a log and keep an eye on things.

 

[Billy the Kid]

Hi all, just throwing this out there to share my recent scare with the dreaded "Propulsion power is reduced" message on 2017 Bolt. 28000 FLAWLESS miles, then one hot summer day (parked in garage, plugged into L2), I hit the remote start to pre-cool. 5mins later, turn ON to drive away and get the message (and service car symbol). Like I said, it had been PERFECT until then, so I was pretty startled. As I drove through my neighborhood it didn't seem weak, so I thought "maybe it was just a little hot from sitting in the garage, it'll probably go away once it cools off a little". But no, eventually I realized that power really was very much reduced and it wasn't really safe to drive. Parked it, then later that night (cooler temps), powered on and drove around just like normal - but the service car light still illuminated.

I used my OBD code reader and got a few codes, but little/no info anywhere. A few sounded like scary dead battery or main fuse problems. Anyway, the dealer took it in, "reprogrammed" something, and gave it back. It's been totally fine ever since (weeks of driving, all conditions and charge levels). I'll copy the service verbiage below, hopefully this helps someone in the future:

"Corrected by drive motor power inverter module reprogramming with SPS. Found DTC S P0AC4, P0AEE, P0BD2, P0BDC. Inspected and reprogrammed HPCM per TSB 18-NA-064 to correct. SPS code 17YN24133339."

Also wondering if anyone here can get their hands on that TSB, curious what it says...

I recently purchased a brand new 2020 bolt and a similar issue happened to me. I was driving to work last week when the service car symbol appeared. I pulled over and got on star to pull the code - P16EA. The car went into reduced propulsion power mode after I continued driving to work. I was really bummed out because the car is only a couple of weeks old with ~2000 miles and already throwing a code. I took my bolt into the dealership and after 1 week of ‘diagnosis’ they told me they were instructed by Chevrolet to reset the code and that I could pick up my car - they said that if the issue comes up again, the HPCM would have to be replaced. I got to the dealership, turned on the car, and the service car symbol appeared immediately....

All this to say, I’m really frustrated and I suspect some greater issue to be causing all of this. Maybe a faulty battery? I will be sure to update you with the outcome of my broken bolt.. I’m wishing I dished out the extra money for a model 3 at this point.

 

[Riderice]

FWIW, I'm at 56k miles now on my 2017 with no further issues of any kind. My Bolt has been the lowest maintenance, best value, most pleasant car I've ever owned and driven.

Hopefully it's something that your dealer can eventually find and fix. 12v battery and fuses is a great place to start, as others mentioned.

And sorry but LOLZ if you think "paying more for a model 3" ( or any Tesla) will somehow guarantee a less frustrating experience. Unfortunately there will always be lemons with any brand/model.

 

[megalexis]

I recently purchased a brand new 2020 bolt and a similar issue happened to me. I was driving to work last week when the service car symbol appeared. I pulled over and got on star to pull the code - P16EA. The car went into reduced propulsion power mode after I continued driving to work. I was really bummed out because the car is only a couple of weeks old with ~2000 miles and already throwing a code. I took my bolt into the dealership and after 1 week of ‘diagnosis’ they told me they were instructed by Chevrolet to reset the code and that I could pick up my car - they said that if the issue comes up again, the HPCM would have to be replaced. I got to the dealership, turned on the car, and the service car symbol appeared immediately....

All this to say, I’m really frustrated and I suspect some greater issue to be causing all of this. Maybe a faulty battery? I will be sure to update you with the outcome of my broken bolt.. I’m wishing I dished out the extra money for a model 3 at this point.

Mine also died at 1500 miles 2020 premier. On day 3 nothing from service. I have 0 car they don't seem to care.

 

[Billy the Kid]

Mine also died at 1500 miles 2020 premier. On day 3 nothing from service. I have 0 car they don't seem to care.

Man, sorry to hear that. Do you know what code your car had? My dealer ordered the hpcm replacement but it hasn’t shown up yet. Your car should be covered under the 3 yr/36000 mile if you bought brand new car.

 

[EV Engineering]

That is helpful, thanks! I had been considering buying TorquePro (and bluetooth plug) to investigate my cell voltages... But I rarely get below 25% or even 50% charge so I don't know how obvious the problem will be yet, if there's a single cell dying somewhere in there...




I'm not one to defend any dealership of taking credit (and/or money) for service they didn't provide, but in this case I'm sure they did reprogram the HPCM - either to mask a real problem, or to prevent false detects of a non-issue... The car had already been charged for many hours, but still plugged in sitting in a stuffy 115-120 degree garage, running the AC for a few minutes.

Good advice at this temperature is to keep hood open so whenever AC is running to cool down electronics or battery so it don't elevate under hood temperature that is already high enough for 12V battery.
Even around 90°F if you call for just cabin AC to cool to 72°F and standing still will quickly elevate under hood temperature above 150°+F .
I have done multiple tests and reason behind is that front undercarriage is very well covered for low drag efficiency while driving and creating vacuum to help with air flow while driving. But it is not helpful while standing still running AC or charging in hot weather.

 

[L Perez]

I have a 2017 Bolt and yesterday I experienced this "propulsion power reduced" issue. In my case the car would not allow me to place it into drive or reverse. I left it in the business location until the next morning and then tried to power on and drive again and it worked. Later that day though it happened again, so I had the 12V battery tested and it was fine.

This seems like a known issue with Chevy Bolts. My Bolt is now sitting in front of a client's house about 25 miles from the nearest dealer. I think GM should be responsible for the towing and fix of this issue since it is a known issue. I will call the dealer in the morning and have them come get the car.

Any advice would be greatly appreciated!

LP

 

[MichBolt]

I have a 2017 Bolt and yesterday I experienced this "propulsion power reduced" issue. In my case the car would not allow me to place it into drive or reverse. I left it in the business location until the next morning and then tried to power on and drive again and it worked. Later that day though it happened again, so I had the 12V battery tested and it was fine.

This seems like a known issue with Chevy Bolts. My Bolt is now sitting in front of a client's house about 25 miles from the nearest dealer. I think GM should be responsible for the towing and fix of this issue since it is a known issue. I will call the dealer in the morning and have them come get the car.

Any advice would be greatly appreciated!

LP

Have you had the battery replaced, or is it still on the original battery? If the battery has been replaced, check the coolant levels in the coolant reservoirs under the hood. See item 7 in the stickied summary and timeline post in the recall section:

Fire recalls summary and timeline - Updated 2/15/22

Timeline from the following: https://www.nhtsa.gov/vehicle/2017/CHEVROLET/BOLT/4%252520DR/FWD#recalls https://allev.info/2021/07/list-of-known-chevy-bolt-fires/ https://www.nhtsa.gov/vehicle/2020/CHEVROLET/BOLT%252520EV/5%252520HB/FWD#recalls 2020-2022 Chevrolet Bolt EV and EUV Defect Notice...

www.chevybolt.org

When you had the 12V battery tested, was it tested under load, or did they just check the voltage?

When did you buy the Bolt, and how many miles are on it? If it's within 5 years and 60,000 miles, you would still be under the powertrain warranty, and would still have Chevrolet Roadside Assistance for towing to the nearest dealership:

Roadside Assistance | Chevrolet Certified Service

<p>Whether your Chevrolet vehicle is under warranty or not, Roadside Assistance is just a phone call or button-push away. Discover what services it offers here.</p>

www.chevrolet.com

Good luck and let us know what it turns out to be.

 

[L Perez]

Have you had the battery replaced, or is it still on the original battery? If the battery has been replaced, check the coolant levels in the coolant reservoirs under the hood. See item 7 in the stickied summary and timeline post in the recall section:

Fire recalls summary and timeline - Updated 2/15/22

Timeline from the following: https://www.nhtsa.gov/vehicle/2017/CHEVROLET/BOLT/4%252520DR/FWD#recalls https://allev.info/2021/07/list-of-known-chevy-bolt-fires/ https://www.nhtsa.gov/vehicle/2020/CHEVROLET/BOLT%252520EV/5%252520HB/FWD#recalls 2020-2022 Chevrolet Bolt EV and EUV Defect Notice...

www.chevybolt.org

When you had the 12V battery tested, was it tested under load, or did they just check the voltage?

When did you buy the Bolt, and how many miles are on it? If it's within 5 years and 60,000 miles, you would still be under the powertrain warranty, and would still have Chevrolet Roadside Assistance for towing to the nearest dealership:

Roadside Assistance | Chevrolet Certified Service

<p>Whether your Chevrolet vehicle is under warranty or not, Roadside Assistance is just a phone call or button-push away. Discover what services it offers here.</p>

www.chevrolet.com

Good luck and let us know what it turns out to be.

Hello and thank you for the quick response!
The car is still on the original battery. The dealer called us in January to say that we would be getting a new battery and they would notify us when it came in. After waiting over 3 months I called to find out what the delay was about and they said they never ordered the battery and that it would be another 6 weeks before the battery would arrive! So we are waiting...

Its a 2017 with about 37k miles that we bought from a dealer in Florida. It has a CPO warranty but it has been 2 years since we bought it.

The 12V battery was tested under load and found to be in good condition and was then fully charged. I will call roadside assistance to have it towed to the dealer today if it doesn't shift into gear this morning.

Thanks again!

LP

 

[Sean Nelson]

I have a 2017 Bolt and yesterday I experienced this "propulsion power reduced" issue. In my case the car would not allow me to place it into drive or reverse.

I've had one occasion in almost 5 years with my 2017 Bolt where the car wouldn't start up properly and I solved it with the "10mm reset" (use a 10mm wrench to disconnect and reconnect the ground terminal of the 12V battery to force a reboot of the car's computers). In a situation like you described it would be one of the first things I'd try in order to get going again.

 

[Riderice]

Its a 2017 with about 37k miles that we bought from a dealer in Florida. It has a CPO warranty but it has been 2 years since we bought it

Even with those low miles, a 2017 Bolt in FL means 5 years of hot 12v-battery-melting heat. And even tho the 12v here is theoretically very under-stressed compared to ICE cars, doing the “10mm reset"(👌👍) or even popping in a new battery would be prudent first steps. Maybe a simple disconnect & reconnect would've worked just as well when I had my original "power reduced" issue...? (FWIW I replace my gas car batteries every 3-4 years, Colorado exposes cars to extreme hots AND colds, very hard on them. I replaced my Bolt 12v battery after about 4yrs, cheap insurance against having to ask a friend or worker to "jump start" my EV🤣)

Summitracing has them for about $155, ACDelco 88866037 Gold Automotive AGM

 

[isissheba]

Has any Bolt that had the "propulsion power reduced" issue been fixed? My 2020 Bolt got the message 5 weeks ago. Following the message first the AC dies and then the battery stopped charging, even though OnStar said the battery is fully charged. The car has been at the dealer since then. The EV Concierge says there is no solution, and they are working on the problem. They have no target date. Based on the discussions above, I would have expected a fix for this problem long before now.

 

[MichBolt]

Has any Bolt that had the "propulsion power reduced" issue been fixed? My 2020 Bolt got the message 5 weeks ago. Following the message first the AC dies and then the battery stopped charging, even though OnStar said the battery is fully charged. The car has been at the dealer since then. The EV Concierge says there is no solution, and they are working on the problem. They have no target date. Based on the discussions above, I would have expected a fix for this problem long before now.

I've read one or two cases where the dealership cleared the code and returned the Bolt to the owner, but that's not technically a fix for the problem (it could return).

As far as I've heard on the forum, the permanent fix is still pending. Latest TSB is PIP5850C:

Code P0BBD

Essentially the same thing has happened to me. Battery replaced several months ago, driving perfect. Got the Propulsion Power Reduced message. Dealer has had my car for 3 weeks because service bulletin said to "separate car from customer' (or something to that effect) with no idea when I might...

www.chevybolt.org