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If refilling a standard setup then use Dot 4 brake fluid.

If refilling a system with braided hoses then use Dot 5.1 fluid.

Start by removing the bonnet bin using a 2 pence coin or similar.

Remove the reservoir cap from the top of the brake master cylinder.

We would advise against using a pressurised self bleeding kit (such as the ezi-bleed) as we found the pressure required to push the fluid through the kit, was just too much for the brake level sensor on the top of the reservoir, and caused the fluid to spill out.

The convention to bleed the brakes is to start with the brakes furthest from this cylinder.

Because of the way the brake system runs in the smart, this is the o/s/r brake.

For ease of access I removed each wheel in turn.

Locate the bleed nipple on the back of the rear drum, it should have a small rubber protective cap on, remove this.

Attach a length of hose with an id of 5mm to the bleed nipple, and put the other length into a suitable container. Use a 7mm spanner to turn the nipple, a small turn of about 90 degrees will suffice.

Get someone else to pump the brake pedal 5 or 6 times, to flush any air out, or if you are changing the fluid, it will flush through a different colour.

When the air is removed, and/or the fluid is flushed through tighten the bleed nipple, and carefully remove the pipe and reattach the protective cap.

Remember to make sure the reservoir is topped up at all times.

Next on the circuit is the n/s/r brake, repeat as per the o/s/r.

Just remember the spanner will turn the opposite way to before!

Following the rears is the n/s/f brake. The bleed nipple is located just above centre of the calliper towards the back edge. Connect the bleed hose and spanner, as before, and again, please keep topping up the brake reservoir.

Finally the o/s/f is bled in the same way.

Remember to refit all of the protective caps, and make sure the reservoir is topped up.

You should be aware that the ABS pump will NOT have been bled by this method. Neither will it have got air in the system.

To bleed the ABS pump you must take the car to Mercedes where they open up the ABS pump valve electronically. They charge half an hours labour for a brake fluid change.

*** Pump brake pedal with ignition on before driving ***

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