IsItAGoodCar

Common Problems with the
2003–2005 Smart Roadster (452)

We've identified 3 known issues that can affect the 2003–2005 Smart Roadster (452). 2 of these are serious faults that could be expensive to repair.

3
Known Issues
2
Serious
0
Moderate
1
Minor

All Known Issues

Catastrophic Water Ingress

SeriousBodywork & Rust

Water enters through wing mirrors, door seals, the bulkhead, and the rear quarter lights. This often ruins the SAM unit and the carpets.

Most affected: Roadster, Roadster-Coupe

Estimated cost: £100–£1,500Affects: 2003–2005Often appears around: Age-related

Typical symptoms

  • •Wet carpets
  • •Mist on the inside of the glass
  • •Electrical gremlins (wipers, lights, starting)

What to inspect before you buy

  • ✓Lift the carpets and feel the foam backing for water
  • ✓Check the SAM unit for white/green powder (corrosion)

SAM Unit Failure

SeriousElectrics & Electronics

Water tracks down the wiring loom from the wiper tray and enters the SAM unit. This is the most common cause of "dead" Roadsters.

Most affected: All Roadster models

Estimated cost: £500–£1,200Affects: 2003–2005Often appears around: Any age

Typical symptoms

  • •Horn sounding continuously
  • •Car won't turn off
  • •Total electrical failure

What to inspect before you buy

  • ✓Check for the "Evil Twin" modifications (drip loops and covers) to protect the SAM

Snapped Aircon Pipes

MinorElectrics & Electronics

The AC pipes are prone to vibration-induced cracks, leading to total loss of refrigerant.

Most affected: All models with AC

Estimated cost: £250–£400Affects: 2003–2005Often appears around: 30,000+ miles

Typical symptoms

  • •AC not cold
  • •Visible oily residue on the pipes near the compressor

What to inspect before you buy

  • ✓Check if the updated flexible AC pipes have been fitted

Buying Tips for the 2003 Smart Roadster (452)

  • ✓Assume the car leaks unless proven otherwise. Water ingress is the Roadster's biggest enemy.
  • ✓Check the SAM unit (behind the dash) and the ECU (on the airbox) for signs of water damage.
  • ✓The soft top (canopy) can shrink over time; check that it seals properly at the side rails.
  • ✓Listen for the turbo "whistle"; a loud siren noise indicates a failing turbo.

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Other Smart Roadster (452) Year Periods

2003–2005

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