IsItAGoodCar
Reliability Guide

Common Problems with the
2020 Citroën C3 (Mk3)

The 2020 facelift added sharper LED lighting and a refreshed cabin, while the 1.5 BlueHDi became the diesel mainstay and the C3 You trimmed the range for value buyers.

What changed for 2020

  • •Revised front end with LED headlights and new tail-light graphics
  • •1.5 BlueHDi 102 now the main diesel, alongside PureTech petrols with manual or automatic
  • •C3 You entry model from 2023 and the C3 Origin run-out after the 2024 Mk4 launch

Common MOT watch-outs

  • !AdBlue and NOx-sensor faults on 1.5 BlueHDi cars, often with engine warnings
  • !Corroded front brake discs and pads on lightly used late cars
  • !Rear shock absorber misting and worn rear axle bushes
4
Known Issues
2
Serious
1
Moderate
1
Minor

All Known Issues

1.2 PureTech "Wet Belt" Degradation

SeriousEngine

The timing belt runs in oil and can degrade, shedding debris that blocks the oil pickup. This leads to oil starvation, vacuum pump failure, and a dangerous loss of braking assistance (Recall R/2020/331).

Est. Repair Cost: £600–£1,800
Warning Signs:

Low oil pressure warning, Hard brake pedal, Engine fault light, Furry/cracked belt visible through filler cap

What to Inspect:
  • Check belt condition via oil filler cap
  • Verify 0W-30/0W-20 oil usage
  • Check recall status
Verified by IsItAGoodCar Research Team

AdBlue Tank and Pump Failure

SeriousFuel System

The AdBlue system on BlueHDi diesels is prone to pump failure, often requiring a full tank replacement.

Est. Repair Cost: £800–£1,300
Warning Signs:

"UREA" warning light, Engine won't start countdown

What to Inspect:
  • Check for emissions warning lights
Verified by IsItAGoodCar Research Team

Exhaust Back Box Detachment

ModerateExhaust & Emissions

The exhaust back box support rod or joint can corrode prematurely, causing the muffler to hang low or detach entirely.

Est. Repair Cost: £150–£300
Warning Signs:

Sudden increase in exhaust noise, Rattling or dragging sound from the rear, Exhaust hanging visibly low

What to Inspect:
  • Inspect exhaust hangers and joints for heavy corrosion
  • Gently shake the tailpipe to check for security
Verified by IsItAGoodCar Research Team

Reversing Camera Calibration and Faults

MinorElectrics & Electronics

The factory-fitted reversing camera can lose its calibration guide lines or show a misaligned view of the bumper.

Est. Repair Cost: £50–£150
Warning Signs:

Missing parking guide lines, Camera view appears off-centre or zoomed in, Intermittent blank screen when in reverse

What to Inspect:
  • Check camera view for clarity and alignment
  • Ensure reversing lights are working (linked to the same circuit)
Verified by IsItAGoodCar Research Team

Buying Tips for 2020 Citroën C3 (Mk3)

  • Drive a BlueHDi until fully hot and watch for UREA or emissions messages
  • Check whether a C3 Origin is the reduced-equipment run-out model before comparing prices
2018–20192021
Check a 2020 Citroën C3 (Mk3) by Registration