Police say half the cars they stopped in an operation to see how many were ready for winter had problems.
Operation Uplift ran for three weeks from the end of October, with checkpoints manned by officers and officials from the vehicle testing centre.
They stopped a total of 276 vehicles - of which, 138 had some form of defect, with 105 faulty lights, and 44 worn tyres.
Seven drivers were issued with a court summons, while five drivers were arrested for drink or drug driving after failing tests.
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