How Do I Know If It’s MHD?

How Can I Tell If The Car Is An MHD?

The Badge

Originally this was easy, you just looked on the boot panel for the MHD logo.

However, people like to de-badge the cars to make them look cleaner. Also, people remove the badge to try and trick people into thinking it’s not an MHD.

The Switch

The next way is to look for the MHD ECO button just in front of the gear stick.

If it has this switch, it’s an MHD. However, there have been cases of these switches also being removed to trick buyers.

The Speedo

When you turn the MHD-equiped fortwo ignition on, you should see ECO show up on the dash.

However, it’s easy to desolder the LEDs, cover them over or change the speedo. This could and does happen. Again, to fool people into buying the car.

Vehicle Identification Number (VIN)

Each car has a unique number that is really hard (and ultimately pointless) to replace. The VIN code can be found in a small window in the lower right hand side of the windscreen…

…and on a sticker in the door shut.

You can assume that this number is correct and with the first 6 numbers will tell you all you need to know.

If the VIN starts with the following numbers, it is an MHD.

451334 (coupe)
451434 (cabrio)
451380 (coupe)
451480 (cabrio)

Between October 2007 and October 2008, the MHD system was available as an optional extra. Very few were sold with this extra but they had the codes 451334 and 451434.

From October 2008, the MHD became standard and you could no longer buy the non turbo model without MHD. These models came with the codes 451380 and 451480.

The Owner’s Document

In the UK, the owner’s document is called the V5C. I’m sure it’s called other things in other countries.

On the document is every piece of information you require about the car. What we are looking for is the emissions in CO2 g/km. If this figure is 97, 98 or 100, you have an MHD. All other petrol models start at 112 and go upwards from there.

Cost Of Road Tax (UK only)

In the UK, the road tax is now called VED so they didn’t have to spend the money actually fixing the roads.

If your petrol smart 451 has free UK road tax, it’s an MHD. All other petrol 451 models are £30 to £105.

Why Should I Care If It’s An MHD?

Read this.

What Does MHD Do And How Does It Work?

With the automatic stop-start function, the running engine is switched off when you step on the brake pedal and the car is stationary. This can be useful if, for example, you are standing at a traffic light or driving in stop-and-go traffic. The stop-start function is automatically activated when you start the engine with the key.

You step on the brake pedal.
The vehicle speed is lower than 5mph (8 km/h)
The temperature of the engine is higher than 60 degrees
The vehicle’s battery is sufficiently charged
The temperature of the battery
Outside temperature are higher than −5 degrees
Forward gear or N is engaged
The vehicle speed was once higher than 8 km/h after the vehicle was started for the first time
The tailgate is closed.

The engine will start again when you release the brake pedal or accelerate.

If you move the gearshift lever from R to 1 or A when maneuvering the vehicle, the stop-start function is only available again after a speed of 5mph (8 km/h) is exceeded. During this time, the yellow control lamp lights up in the instrument cluster. The indicator lamps in the instrument cluster show the status of the stop-start function.

Indicator lights

Green ECO illuminatedThe stop-start function is switched on and active.
Yellow ECO illuminatedThe stop-start function is switched on but not yet active.
Yellow ECO flashes for about 10 seconds and then goes outStop-start function is disturbed.

The engine will restart automatically when:
You manually switch the function off with the button on the center console or open the tailgate while the vehicle is stationary.
The green / yellow control lamp in the instrument cluster goes out. The vacuum for the brake booster is too low. The speed is higher than 6mph (10 km/h).