The Smart 451 ED has 2 batteries, well, it acually has 94 batteries but 93 of them make up the 400v drive battery. It also has the standard 12v lead acid battery that you'd normally get in a petrol and diesel smart. It's this battery that runs all of the electronics...
Smartmods
for all your modding needs, recommended by Evilution
Kane Harrison
451 ED 22Kw Charger Info
Everything You Didn't Know About The Brusa 22kW 451 Charger ...and didn't really want to know. This is the 22kW charger box found in the 451 ED. Apparently it was the 1st 22kW in an electric car. It's bigger than you think too. It's nearly half a metre wide. It has 2...
451 ED Battery Cell Charging
Traction Battery Voltage The 451 ED 400 volt traction battery contains 93 separate cells, all wired in series. At an absolute maximum, lithium ion cells should be charged to no higher than 4.2 volts. 93 cells at 4.2 volts = 390.6 volts but they call it a 400 volt...
451 ED Desiccant Cartridge
What Is A Desiccant Cartridge? Electric doesn't like water but high power batteries and water can cause serious issues. A desiccant cartridge pulls all of the water out of the air inside the battery. This reduction in humidity stops the formation of condensation...
451 ED Heater Fault
A new common problem started appearing quite regularly on 451 Electric Drive Fortwos, the heater stopped heating. Sometimes it'll work for a while and stop working again. The issue here is that when you own an electric smart, if you want to use the heater, you must...
451 ED HV Battery Opening
This is the high voltage battery removed form a 451 electric drive fortwo. It's 178kg of nearly unmovable nightmares. All around the outside, if you look carefully, there are discoloured spots along the outside lip. I have marked them yellow below. The discolouring is...
451 ED HV Battery Removal
This job isn't to be taken lightly. You will need some specialist equipment but it can be done at home in your garage if you really have to. Step 1 is that you have to lift the car high enough so you can get the battery out on some sort of trolley. If you have a...
451 ED HV Disconnect Plug
If you are doing any electrical work on your 451 ED, you really should disable the high voltage battery. This is easily done. Make sure the car is turned off before disabling the HV battery. Look underneath the dashboard, next to the fuse box. See the red plug, pull...
451 ED HV Mega Fuse
If you have a catastrophic high voltage electrical failure, the battery has a safety feature to stop all of that fire, sparks, screaming, running around and gnashing of teeth as everything in the local vicinity also sets on fire. This fault could be a damaged HV cable...
451 ED Inverter Removal
One night, late in 2022, I got in my 9 year old 451 ED and turned the key to start it in order to drive to work. Despite the car being in park and the handbrake on, the car lurched backwards an inch and all the error lights came on the dash. I tried removing and...
451 ED Noise Maker
Electric Smarts Make A Noise In many countries, the Government have panicked and demanded that all electric cars make a noise. This noise is a pedestrian warning for idiots who don't look before crossing the road. Smart call it an Acoustic Presence Indicator. Other...
451 ED Onboard Charger
I'd been driving my 2013 451 ED for over 4 years with very few issues. Once a year it would cut out but restart with no issues immediately. The error code was about the contractors and they were quite loud when they closed. Then in Q3 2022 I started getting a warning...
451 Electric Mirrors Retrofit
Important Note If your 451 was built from 12/2008 onwards, this job is going to be much easier. If your 451 was built 11/2008 or before, the extra nonsense is nailed onto the end of this page. You Will Need 2 new door wiring looms with the appropriate connectors. A...
451 Electric Mirrors Wiring
Key:
E = Earth
C4/8 = Connection plug 4, pin 8
Fuse* or F* = Direct connection fuse number
Black Yellow = Wire colour
Modules are labeled in the picture.
451 Electric Window Wiring
Key:
E = Earth
C4/8 = Connection plug 4, pin 8
Fuse* or F* = Direct connection fuse number
Black Yellow = Wire colour
Modules are labeled in the picture.
451 Electrical Connectors
Accelerator Pedal AC Pressure sensor Aerial Airbag Controller Airbag Switch Blower Motor Brake Fluid Level Switch Dash Button Bank Door Connector Cabin Heater Duct Temperature Sensor ECU Secondary Engine Connector Front Fog Lights Front Radiator Fan Gearbox Controller...
451 Engine Mount Change
The 451 engine mount suffers badly from wear which allows too much engine movement, swapping it is very easy.
451 Engine Mount Repair
The engine mount for the 451 is quite poorly designed and splits causing the engine to move a lot.
Considering the cost of a new front engine mount you may as well just repair the original one.
451 ESP Controller Pin Out
The traction control (ESP & ABS) controller is attached to the side of the ABS pump underneath the car. It's shielded by the plastic undertray for protection. It's easily recognised by the several hard brake pipes coming from the unit. Pin Number Wire Colour...
451 ESP Removal
In case you need to spin the wheels to get you out of snow and ice or if you are running your car on a dyno, you need to disable the ESP system.