Smart Electric main battery cuts out while in motion

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I’m from the UK. I’ve got a November 2013 Smart ED fortwo. This is actually our second as we had a prototype between 2010 and 2014.
Last year we had two incidents where the main battery shut down while driving at about 30 mph driving and once while waiting to make a right turn. Something was shutting down the main battery because the smaller battery continued to function. The message comes up ‘driver system engine failure’ and there is a lot noise and flashing of lights. On the two occasions I was in motion I could cruise into the side of the road and it restarted. On the occasion it ‘stalled’ at the junction it took about 5 efforts.

It was shipped to Mercedes Brooklands (near Woking, UK) who have been dealing with these since they first arrived in the UK. It’s an intermittent fault so diagnostics were inconclusive and no fault was found. The conclusion by the technical guys was that there was a problem with the driver control unit (I think that’s what they called it). So it was replaced last autumn for about 500 sterling.

Then yesterday with no warning and while driving I sensed a few occasions that I was losing power and when I drew up at a friends the main battery switched itself off again and I got the flashing red etc ‘driver system engine failure’. The journey home wasn’t great, there were a couple of major lurches but it kept going.

Obviously I need to speak to Brooklands again but I’d be really interested to know, am I just unlucky, or is this a recognised problem?


That sounds pretty serious – either its a major software problem, or something is going wrong in the battery pack. How many miles are on it?

Has it been wetter than usual?


Thanks for responding. It is serious. Car grounded. I am not even prepared to drive it the 20 or so miles to the dealer.

The main battery had a full test last year and is fine, plenty of life in it and has only done about 12,000 miles.

And no, wet weather not the problem as we are having a particularly dry spring this year.

I am about to engage seriously with Smart and will post the outcome.



Hi, This same thing happened to me several times recently. I brought it to the dealership, they took it for a drive and said it didn’t happen to them and suggested that a recall they completed probably would fix the problem. Of course the same thing happened again – several times again, with a couple of jolts thrown in. I brought it back and left it there for a few days hoping to get an answer. Here’s what I got:
“Performed short test found communication faults present. Cleared stored faults and performed several road tests. Could not confirm customer complaint. Faults have not returned.” The mileage in and mileage out was the same but I’m assuming they did take it out since I called for updates repeatedly. I have concluded they have no idea what’s wrong and don’t want to deal with it. I hope you may have some helpful information, otherwise, I guess my next step is to contact MB headquarters with this problem. You and I can’t be the only ones to experience this. I don’t feel safe in this car any more.

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