MOT failure · RFR #30536
Warning device shows system malfunction
Total
6,707
Models
54
Models most at risk.
Ranked by rate, not raw volume. A Fiesta shows every failure a lot because there are a lot of Fiestas. Rate = share of that model's own MOTs.
Failure match · your reg
Does this failure affect your car?
Enter your reg and we'll check whether your model appears on the affected list — and where it ranks.
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- 01 Chrysler Jeep Patriot 4.47%
- 02 Chrysler Voyager 3.17%
- 03 Chrysler PT Cruiser 3.16%
- 04 Peugeot 407 2.91%
- 05 Chevrolet Kalos 2.87%
- 06 Volvo S70 2.53%
- 07 Renault Grand Espace 2.47%
- 08 Volvo 800 Series 2.45%
- 09 Chrysler Jeep Grand Voyager 2.36%
- 10 Renault Espace 2.34%
- 11 Chrysler Jeep 300 2.22%
- 12 MG GS 2.21%
- 13 Dodge Nitro 2.21%
- 14 Hyundai Coupe 2.21%
- 15 Ldv V80 2.20%
- 16 Hyundai Terracan 2.18%
- 17 Chrysler Grand Voyager 2.07%
- 18 Jaguar Xk8 1.90%
- 19 Chrysler 300 C 1.45%
- 20 BMW Z3 1.41%
- 21 BMW 840 1.34%
- 22 Volkswagen California 1.32%
- 23 Chrysler 300 1.20%
- 24 Mercedes Benz CL 500 0.90%
- 25 Mercedes Benz CL 0.89%
- 26 Porsche 968 0.85%
- 27 Jaguar Xkr 0.84%
- 28 Honda Integra 0.79%
- 29 Vauxhall Vx220 0.71%
- 30 Mercedes Benz 500 0.71%
Top 30 by rate. 24 more models also logged this defect.
Cost orientation
Hard to predict in isolation — depends what's actually worn.
This defect doesn't map to a clean retail-part swap; ranges vary too widely without seeing the car. Use the estimator to bracket the all-in cost across the items most likely to surface alongside it.
Frequently asked.
- Why does warning device shows system malfunction fail an MOT?
- Warning device shows system malfunction. Most commonly flagged on the Chrysler Jeep Patriot. UK MOT standards require this item to meet minimum safety thresholds — when it falls short, the tester logs it as a Major or Dangerous defect and the car fails outright.
- How much does it cost to fix warning device shows system malfunction?
- Costs vary depending on the vehicle, region, and severity. Use our MOT cost estimator for typical UK garage rates across the most common failure items.
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