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Discussion Starter · #1 · (Edited)
EVERY report that I can recall of 500e so-called "battery pack failure" happened suddenly overnight :unsure:.

Consider how the battery dies in your phone or laptop: Very gradual capacity loss over years.

The "dead" cars all drove home fine, then were suddenly "dead" in the morning with no vital contactor "clunk" to connect the battery pack. They were eventually towed to a dealer where diagnostics showed a fault in the battery pack which contains the contactors.

Now 2 more users (HUGE thanks to @MDMTahiti for being first) have reported complete failures with no "clunk" so their cars wouldn't start OR charge. Instead of towing them to a dealer, they re-enabled the contactors with AlfaOBD (click here for OBD connection tips) & the cars work fine:
Rectangle Slope Font Line Water

Click the thumbnail below for enlarged version:
Rectangle Slope Font Line Water

First report click here.
2nd report click here.
 

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Discussion Starter · #2 · (Edited)
Sudden lithium-ion death apparently requires overheating or overvoltage, but those are both prevented by our cars' cooling & charging systems, which keep it cool & limit the voltage to less than 90% of true full capacity.

Even IF they were killed by heat, that would be LESS likely to happen charging at night when it's colder. But I don't recall ANY reports of total failure after daytime charging.

Even sudden overnight failure of the contactors seems extremely unlikely. They're electromagnetically-actuated switches, like a gas car's starter solenoid. If I recall correctly, they typically start to take 2 key cycles before working, then 3 or more cycles for a while, before finally failing. Not functioning perfectly to drive home, & the next morning suddenly failing completely.
 

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Discussion Starter · #3 · (Edited)
I do remember ONE report, from EUROPE, where I think a car stopped when a cell died while driving, due to damage by extended storage unplugged during transport. Of course that's an unusual case, similar to the report of cell damage from parking for I think about a year plugged into a charger that lost power due to a GFCI breaker tripping.

There are also many reports of the 12V starter battery gradually losing capacity until it's finally insufficient to activate the contactors. That FEELS "sudden" but in reality it just went from initially having WAY more capacity than needed, very gradually dropping to a lot more than needed, then a little more than needed, etc. You don't notice until it finally drops below the needed capacity, since unfortunately our cars' 12V warning usually comes too late. That's why I added my own volt gauge to monitor it:
Hood Automotive tire Bumper Vehicle Motor vehicle
 

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Discussion Starter · #4 ·
Now there's a 3rd report of total failure, corrected by the OBD reset in post #1 above.

This 3rd failure was posted by "Peter_K" on the "other" forum:

"Same problem, no clunk. I used AlfaOBD to re-enable the contactors and the car charges and runs...
AlfaOBD reported no present faults, so I cleared the old ones before re-enabling the contactors.
Didn't disconnect the humidity sensor on the principle of minimizing change if things were working...
This time, rebooting didn't work, but re-enabling the contactors using AlfaOBD seems have done the trick.

Thanks for the tip.... "
 

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Here was my situation a few days ago. It got to -20F here in Minnesota. Went out to my car to go to work, and... my car would not start. Not clunk from the contactors. I have a small voltmeter that resides in the cigarette 12V power port in the car and I could visually see that the voltage was 12.4 volts. So the 12V battery is holding up. Cycled the key many, many times and no clunks. Plugged the ChargePoint Level 2 EVSE in several times. No clunks. Plugged the 120V portable OEM EVSE in several times. No clunks.

So I waited two days until we had a heat wave of 10F (sarcasm). Got out my 12V battery charger/booster and was measuring 13.6 volts on the system. Still no clunks. By now I am pretty worried thinking my car is dead and is going to need to get towed to a dealer. ($$$$)

So I dug out my PC that has the latest paid version of AlfaOBD and the OBDII to USB adapter. Went through module by module looking for errors. Found a couple.

EVCU log:
___
Reading faults for: Electric Vehicle Control Unit (EVCU)
___
Faults reported:

1/8/2022 2:53:19 PM
Faults found.
B23B0
___
Error code: B23B0
BPCM Fault

Test completed
Error intermittent
Failure warning lamp 'ON': Not requested
___

BPCM log:
___
Reading faults for: Battery Pack Control Module (BPCM)
___
Faults reported:

1/8/2022 1:53:34 PM
Faults found.
P1E25
___
Error code: P1E25
Hybrid/EV Battery Failure Level 2

Last test completed unsuccessfully
Error present
Failure warning lamp 'ON': Requested
___

Tried clearing the faults, but the fault would come back.
So... decided to start running through some active diagnostics.
Started with HV Balance and Isolation tests.
Continued on with HV contactor tests. Here is said I needed to pull the HV disconnect, which I never did. I also did not hear any clunks.
Reset Weld Check Fault.
Finally did the Enable/Disable HV Battery Contactors. Again the directions say to the pull the HV disconnect, which I never did. Did not hear any clunks either, so I figured that maybe the HV disconnect needed to be pulled to make these tests work. But I never got that far...

I decided to cycle the key again before going through the HV disconnect pull procedure. And surprise! I hear the clunk!

Car has worked fine now for several days.

So what caused this? Not sure. But trying to start it when it was -20F may be part of what caused the issue.

Being a bit leery, of possible further issues, I have decided to change my charging procedure. In the past I was charging using my ChargePoint EVSE at the maximum 6.6kW rate. With my battery at 50% charge, it would charge in about 1.5 hours or so, and then the battery would sit and get cold soaked overnight at -20F. So now I have decided to use the 120V OEM EVSE that charges at only about 5% per hour. Now it takes 10 hours to add 50% charge, but at least the battery is now being charged slowly over time and generating a bit of heat to keep the battery from being cold soaked at -20F.
 

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Discussion Starter · #6 · (Edited)
THANK YOU !!

This is now the FOURTH CONFIRMING REPORT!!!

Summary*:
Went out to my car to go to work, and... my car would not start. Not clunk from the contactors.... did the Enable/Disable HV Battery Contactors..... And surprise! I hear the clunk!

Car has worked fine now for several days.

One question for @abenusa : Is your humidity sensor connected?


*@abenusa please correct me if I deleted something that you really feel is relevant.
 

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Here was my situation a few days ago. It got to -20F here in Minnesota. Went out to my car to go to work, and... my car would not start. Not clunk from the contactors. I have a small voltmeter that resides in the cigarette 12V power port in the car and I could visually see that the voltage was 12.4 volts. So the 12V battery is holding up. Cycled the key many, many times and no clunks. Plugged the ChargePoint Level 2 EVSE in several times. No clunks. Plugged the 120V portable OEM EVSE in several times. No clunks.

So I waited two days until we had a heat wave of 10F (sarcasm). Got out my 12V battery charger/booster and was measuring 13.6 volts on the system. Still no clunks. By now I am pretty worried thinking my car is dead and is going to need to get towed to a dealer. ($$$$)

So I dug out my PC that has the latest paid version of AlfaOBD and the OBDII to USB adapter. Went through module by module looking for errors. Found a couple.

EVCU log:
___
Reading faults for: Electric Vehicle Control Unit (EVCU)
___
Faults reported:

1/8/2022 2:53:19 PM
Faults found.
B23B0
___
Error code: B23B0
BPCM Fault

Test completed
Error intermittent
Failure warning lamp 'ON': Not requested
___

BPCM log:
___
Reading faults for: Battery Pack Control Module (BPCM)
___
Faults reported:

1/8/2022 1:53:34 PM
Faults found.
P1E25
___
Error code: P1E25
Hybrid/EV Battery Failure Level 2

Last test completed unsuccessfully
Error present
Failure warning lamp 'ON': Requested
___

Tried clearing the faults, but the fault would come back.
So... decided to start running through some active diagnostics.
Started with HV Balance and Isolation tests.
Continued on with HV contactor tests. Here is said I needed to pull the HV disconnect, which I never did. I also did not hear any clunks.
Reset Weld Check Fault.
Finally did the Enable/Disable HV Battery Contactors. Again the directions say to the pull the HV disconnect, which I never did. Did not hear any clunks either, so I figured that maybe the HV disconnect needed to be pulled to make these tests work. But I never got that far...

I decided to cycle the key again before going through the HV disconnect pull procedure. And surprise! I hear the clunk!

Car has worked fine now for several days.

So what caused this? Not sure. But trying to start it when it was -20F may be part of what caused the issue.

Being a bit leery, of possible further issues, I have decided to change my charging procedure. In the past I was charging using my ChargePoint EVSE at the maximum 6.6kW rate. With my battery at 50% charge, it would charge in about 1.5 hours or so, and then the battery would sit and get cold soaked overnight at -20F. So now I have decided to use the 120V OEM EVSE that charges at only about 5% per hour. Now it takes 10 hours to add 50% charge, but at least the battery is now being charged slowly over time and generating a bit of heat to keep the battery from being cold soaked at -20F.
You used a cable/USB OBD2? I thought that was a no-no with the 500e, people had all sorts of issues after doing that?

Does it require paid alphaobd to reset the contactors?

Sent from my Pixel 3a using Tapatalk
 

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You used a cable/USB OBD2? I thought that was a no-no with the 500e, people had all sorts of issues after doing that?

Does it require paid alphaobd to reset the contactors?

Sent from my Pixel 3a using Tapatalk
It is a recommended OBDII to USB adapter for use with the Windows version of AlfaOBD and MultiECUscan. Works great. I like the Windows version because I can save logs and inspect them carefully.
 

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It is a recommended OBDII to USB adapter for use with the Windows version of AlfaOBD and MultiECUscan. Works great. I like the Windows version because I can save logs and inspect them carefully.
Logs are saved on the android version as well. I don't recall which folder it puts them in, but if you dig around long enough in the file manager you can find them. If I recall, each log gets appended to the file so it can be a bit of work to go through the file.
 

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Discussion Starter · #11 · (Edited)
I disconnected the humidity sensor shortly after I brought the car two years ago.
Thank you! Now we know for sure that it's not caused by the humidity sensor.

That's too bad, in a way, since it means we can't avoid the contactor disable glitch just by unplugging the sensor.
 

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Discussion Starter · #12 ·
Does it require paid alphaobd to reset the contactors?
That's an excellent question, but @abenusa likely doesn't know what the free version does, since he has the paid version.

However I'm pretty sure the free version of AlfaOBD works, since the commands show as active on my own free version.

Sorry that my pic in post #1 above is a bit misleading, showing the commands as inactive light grey since I took those screenshots without connecting to the car. When connected, the commands show as active red & dark grey, like the very last pic in that sequence.

You could check that your own free AlfaOBD shows the commands as active.
 

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So... the bigger question would be "What causes the HV contactors to become disabled in the first place?". I have some theories. Glitch in one of the car computers? Questionable 12V voltage levels that cause a glitch? A contactor that sticks open once or twice and then the computer disables it semi-permanently as some sort of safety measure? It seems plausible in my case in as I tried to repeatedly start it cold soaked at -20F. It sure would be nice if we were able to access an actual software engineer that was on the team that developed the software for the car.
 

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Wow! Thanks for posting. This is valuable information. Very educational.
 

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Discussion Starter · #15 · (Edited)
The fact that we now seem to know how to fix it is good enough for me, but it would be nice to discover a preventable cause.

@abenusa had some good ideas that I've been thinking hard about:
  • Low 12V seems unlikely, since it's even lower by the time a reset is done, but it works after that.
  • A contactor sticking open seems unlikely at the low mileage/age reported, compared to older cars still working fine.
  • Computer glitch seems most likely. Many users, including me, have reported glitches from non-OEM EVSEs. Every failure was in the morning, likely after overnight charging. I wonder if they were all using a non-OEM EVSE!
 

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Discussion Starter · #16 ·
Maybe @abenusa & @MDMTahiti & @witmannerik can post their OBD contactor history so we could prove it isn't actually wear, by comparing to older cars with more cycles that have never failed.

Here's my 2013 with 28.5k miles (click to enlarge):
Font Material property Number Document Screenshot

Closes: 13104
Opens Under Load: 0
PreCharge Failures: 0

ALSO, maybe everybody could report if the last charge before failure was done on the OEM cord or an aftermarket unit, so we could try to see if that's a factor.
 
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