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Electrical guides and mods

453 ED/EQ Battery Fault

Modification Details

There seems to be a software issue with the 453 ED/EQ which can intermittently bring up a battery fault.

The error can display in 1 of 2 ways. Malfunction, Visit Workshop...

...or Charging not possible, Visit workshop.

Photo coming soon

Either way, the car will not start or drive.

Smart Dealers

Smart dealers will come in 1 of 2 catagories.
They will either say they can't find a fault or they'll say they updated the software.

Many people with this problem find that the car doesn't start or drive but once it's been recovered to a dealer, it's ok.

The "Fix"

Many ED/EQ owners have found that waiting 10 minutes (with the car turned off) will allow it to start and drive.
Ensure that everything is turned off. No hazard lights, no stereo, no interior light etc.

Best thing to do is lock the car up and walk away for a while. When you come back, it'll usually start fine.
Others have stated that disconnecting the 12 volt battery for 10 minutes will also work. Leave that as a last resort.

It's probably a good idea to have one of those lithium battery boosters.

What's The Problem?

This is my best guess but I believe it's an issue with the 12 volt battery, not the 400 volt drive battery.

The 12 volt battery (stored under the front service hatch/hood/bonnet) is used to power up all of the electrics.
This includes motor relays, contactors, interlocks, controllers, safety systems and the charger.

The 400 volt drive battery is used to charge the 12 volt battery. It doesn't charge it all the time.
It doesn't even charge it continuously when the car is running.

It seems as though the 12 volt battery doesn't have enough power to initiate the car's systems.

Trying and failing to start the car and then locking it up and walking away forces the car to charge the 12 volt battery.

Long Term Fix?

If you keep experiencing this fault. Fit a new 12 volt battery. This should sort it.

Alternatively, carry a jump starter box. This will boost the voltage enough to initiate the car which will start
the DC-DC in car 12v battery charging. This helps if you don't want to sit around waiting for 10 minutes.

I have these ones but there are several small lithium Ion booster boxes.

Smart Dealer Software Update

Finally! Smart have rolled out a software update that apparently fixes the issue.

This will either lower the voltage 
expected by the car for the active systems, or it'll intermittently turn on the
DC-DC stepdown charger whilst the car is off. This will regularly ensure that the 12v battery is charged.

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