[FART FORTWO]

Guidance needed! I just purchased a 2016 Smart Fortwo in the US&A. It is in excellent physical condition. It sat too long. I'll attach images of the dash warnings & door jam stickers. I am in New York. I was wondering if I should disconnect and/or remove the HV battery immediately or if that matters at this point. My biggest concern is that the temperature is dropping below freezing now that the winter is here. I don't want to waste time trying to learn by watching videos and searching for answers in the forums which I know are probably there. Guide me through the basics please. Thank you very much in advance.

 

[SMARTKAR]

welcome, You will get answer bettered answer in the smart fortwo Electric Drive section

 

[FART FORTWO]

That makes sense. I'll try and delete this and repost it there.

 

[SMARTKAR]

The moderator just might move it to the correct section

 

[Miss Mercedes]

Welcome to the forum! I moved this thread to the Electric Drive section. We have some EV experts that'll hopefully get ya on the right track.

 

[hallcp]

Any chance of cancelling the sale?

 

[Jo e Lefors]

Welcome and Good Luck

 

[Yinzer]

Yes, your best option is to cancel the sale. If you can't, and have the space and DIY skills, you can attempt a de-bricking using the various information and small garage-level businesses that provide BMS reprogramming and parts that can be found in this forum.

Temperatures below freezing are no problem.

Did the 12V battery die?

 

[FART FORTWO]

Yes, your best option is to cancel the sale. If you can't, and have the space and DIY skills, you can attempt a de-bricking using the various information and small garage-level businesses that provide BMS reprogramming and parts that can be found in this forum.

Temperatures below freezing are no problem.

Did the 12V battery die?

It was dead, but, I was able to recharge it.

 

[hallcp]

Letting a smart sit with a dead 12v battery can permanently damage the high voltage traction battery. (A clear design defect.) I would suggest you get it to a Mercedes dealer for diagnosis. Some users have reported quotes of up to $17k for repairs, effectively totaling the car. As Zinzer mentioned, you can find DIY repair attempts in this forum, but it is truly not for the faint of heart and doesn’t always succeed.

 

[Yinzer]

It was dead, but, I was able to recharge it.

Did you charge the 12V battery before you gave the seller your money? Why would someone ever buy a car that does not run and cannot be test driven?

 

[N9QQD]

I bought A 2015 from a used car lot, defective with the same issue, It is fixable, but the battery need to be removed to get to the BMS and current sensor. The German site EQpassion.de has also good info on the battery removal. Look at "EV battery replacement" here in the Forum there is good information in it. So far so good my Smart still drives. Bill Kichman can reprogram the BMS if it does not reset. He is in Pensylvania. I had to send my BMS to Lithuania and i also needed a current sensor from Germany. I dont know if they figured out on how to reprogram the BMS without removing it from the battery. Or having an alternative to the current sensor. Also messing with the battery is dangerous. There is no Off Switch. max 400VDC. The battery weight is about 400lbs

 

[Yinzer]

I bought A 2015 from a used car lot, defective with the same issue, It is fixable, but the battery need to be removed to get to the BMS and current sensor. The German site EQpassion.de has also good info on the battery removal. Look at "EV battery replacement" here in the Forum there is good information in it. So far so good my Smart still drives. Bill Kichman can reprogram the BMS if it does not reset. He is in Pensylvania. I had to send my BMS to Lithuania and i also needed a current sensor from Germany. I dont know if they figured out on how to reprogram the BMS without removing it from the battery. Or having an alternative to the current sensor. Also messing with the battery is dangerous. There is no Off Switch. max 400VDC. The battery weight is about 400lbs

We have never gotten any posts here about a Smart ED being successfully unbricked and the costs and labor involved. So please, if you can, start a new discussion with your description of how you got your Smart back running.

 

[N9QQD]

Check "EV battery replacement" post there is lots of info. I bought the car and the dealer said he bought a Charging cable from Ebay and it did not charge the car. I looked at EQpassion for info. I dropped the Traction battery and removed the 12Volt battery. Both where dead. 12 Volt battery needed a healthy charge and the 3 banks in the traction battery where down at 10 Volts. I made a charger out of an adjustable transformer, rectifier capacitors and some gauges. I charged the traction battery carefully with low current to 3.2 volt a cell. it took week or more charging let it settle checking the individual cells . Now the gauge in the car showed a charge but it did not drive. I bought an AUTEL MaxiDiag MD806 Pro OBD2 reader from Amazon and it reads the Smart car electrical error code and cell voltages. I put the error code here in the forum and on the EQpasssion forum. I had the dreaded P15081C bricked battery code. I paid $500 on EQpassion for reprogramming and an extra $50 so the code does not come back. Moritz told me where to send the BMS. Then I bought for another $500 the current sensor. As I had been told, when the 12 volt battery goes low, a DC/DC converter in the BMS cannot regulate the output voltage and destroys the current sensor. Moritz had some in Germany and sold me one. After I got everything back together the car drove again. But still displayed the error on the dash. I bought an OPENPORT 2.0 OBD2 to USB and Jochen logged into my laptop and deleted the error on my dash. Now the car runs. It is my weekend car. When it was fixed in spring it showed 70 miles on a charge, now I am down to 40miles per charge. I think it the cold weather and my driving style. I have a friend she live 25 miles away and I make it back with 20% left on the charge. I am happy with the car.

 

[N9QQD]

Just to avoid 12 Volt issues again the 12 Volt battery is on a 4 amp charger from Harbor freight when I am not using the car.

 

[Jmk2020]

As N9QQD wrote:
In meantime there are also options in US to fix the BMS ECU in US by Bill which takes out the high costs for transportation and tax to Europe by Bill.
He also did go the long way. If you use the right cheap 120V or 400V powersupply for a few bucks, i supported several approaches to recharge the HV battery and fix the issues within 2-3 days to bring back the car to road again.

In meantime much more knowledge how to bring back the car and the several rootcauses for the issues are known.

So i wonder on Yinzer's comment he never read about finally fixed cars. Even here in the forum several successful approaches where posted and described in details.

If you use google or deepl translation you maybe follow also the German Goingelectric forum and special the Smart ED3 part. There i also wrote expensivly about how to do it.

 

[Yinzer]

Check "EV battery replacement" post there is lots of info. I bought the car and the dealer said he bought a Charging cable from Ebay and it did not charge the car. I looked at EQpassion for info. I dropped the Traction battery and removed the 12Volt battery. Both where dead. 12 Volt battery needed a healthy charge and the 3 banks in the traction battery where down at 10 Volts. I made a charger out of an adjustable transformer, rectifier capacitors and some gauges. I charged the traction battery carefully with low current to 3.2 volt a cell. it took week or more charging let it settle checking the individual cells . Now the gauge in the car showed a charge but it did not drive. I bought an AUTEL MaxiDiag MD806 Pro OBD2 reader from Amazon and it reads the Smart car electrical error code and cell voltages. I put the error code here in the forum and on the EQpasssion forum. I had the dreaded P15081C bricked battery code. I paid $500 on EQpassion for reprogramming and an extra $50 so the code does not come back. Moritz told me where to send the BMS. Then I bought for another $500 the current sensor. As I had been told, when the 12 volt battery goes low, a DC/DC converter in the BMS cannot regulate the output voltage and destroys the current sensor. Moritz had some in Germany and sold me one. After I got everything back together the car drove again. But still displayed the error on the dash. I bought an OPENPORT 2.0 OBD2 to USB and Jochen logged into my laptop and deleted the error on my dash. Now the car runs. It is my weekend car. When it was fixed in spring it showed 70 miles on a charge, now I am down to 40miles per charge. I think it the cold weather and my driving style. I have a friend she live 25 miles away and I make it back with 20% left on the charge. I am happy with the car.

What was the total cost - including the OBD readers?

 

[Yinzer]

As N9QQD wrote:
In meantime there are also options in US to fix the BMS ECU in US by Bill which takes out the high costs for transportation and tax to Europe by Bill.
He also did go the long way. If you use the right cheap 120V or 400V powersupply for a few bucks, i supported several approaches to recharge the HV battery and fix the issues within 2-3 days to bring back the car to road again.

In meantime much more knowledge how to bring back the car and the several rootcauses for the issues are known.

So i wonder on Yinzer's comment he never read about finally fixed cars. Even here in the forum several successful approaches where posted and described in details.

If you use google or deepl translation you maybe follow also the German Goingelectric forum and special the Smart ED3 part. There i also wrote expensivly about how to do it.

Until N9QQD's post here, nobody has provided a descriptive case study of going through the process and the result including materials and costs. It has all jsut been "you can do this, you do can that."

 

[Jmk2020]

The problem is there is not only on common case and solution.
Depending on the case the solution is different. But also Bill was telling how it need to be done. Or the Norway colleague even with the word documentation about 2 years before. The canadian guy also, and many more successful brought there car back on road.

Most critical is, if some cells are not taking charge or degraded too much. To change a cells is the worst work to do.
Also if the current sensor died already during discharge ( or during charge), actual there is no cheap solution.
To fix the P18051C is easy in meantime. Never the less there are some addition failures and dangers, which need to be solved inside the BMS.

The OBD solution with the Openport seems to be the most easy and cheap solution.

So the costs for fixing the HV battery issues could depend from some hours work up to 1000$ -1500$ and beyond. Depending of all puzzle pieces which need to be done. And for sure who helps you or do the job. The given price indications are increased in meantime according the published prices.

 

[N9QQD]

Hi, the total cost for me was less the if I would have bought a running car. BMS repair was $550 plus $80 for shipping via US Postal service. (no tracking outside the US,it got me worried after 2 weeks) Moritz found it and send me the return tracking #. It tracked only in Europe. Another Week of worry (LOL). FEDEX wanted $280 and DHL was a no go. The Autel Scanner was $275. The current sensor was $500.and the open port was $50 I think i am lucky that traction battery recovered and all cells looked healthy, holding the voltage. The charger I build was made from electrical junk I collected, there was no cost to me. As you may see from my username, it is my Hamradio call sign. I like too tinker with electrical stuff. This car just was another challange for me. Total cost for me was about $1425 for the repair. The Autel Scanner works also on my VW. But without Jochen's knowledge and help and the info on EQpassion and the part from there, I may not have gotten the car to work.