New driver’s fury over GPS tracker

and rewards careful driving. If I speed, brake or accelerate suddenly, I can be classed as a bad driver and the price goes up.”

But the day after the box was fitted, the car wouldn’t start.

Gavin, of East Kilbride, said: “It’s a four-year-old Fabia Monte Carlo. We’ve had it in the family for 10 months and it has never missed a beat.”

He called the AA, who issued a report stating the black box was causing the voltage to the fuel pump to drop.

The car was towed to a dealer where a new fuel pump and regulator were fitted and he picked it up. But the following day, it wouldn’t start again.

He said: “This time the mechanic at the dea ler suspected that the black box, which was hardwired to the car’s electrics, was burning the fuel pump out.

“He disconnected it before fitting another new fuel pump and sensor and road-tested it over a period of three days before I picked it up. It has been running fine since.”

He contacted Co-op to explain but they claimed he was in breach of contract for having the box disconnected and cancelled his policy.

Gavin said: “They said I had broken the law. But both the mechanic and the AA patrolman were adamant the box had caused the problem. Co-op are refusing to refund my £ 400 deposit and are talking about charging a cancellation fee.”

I got on to Co- op and they apologised, reinstated the insurance, arranged for another box to be fitted and paid Gavin £400 to say sorry.

Their spokesman said: “While our suppliers do not believe the black box installation could have caused the issue, we didn’t have the opportunity to investigate prior to it being disconnected.

“We have reimbursed Gavin for the AA charges and for the cost of him being put on his sister’s policy. He has decided to continue to be insured with us.” 72, who has Alzheimer’s, said: “Karen is my attorney but each time she called on my behalf she was passed from pillar to post.

“Nobody would authorise the refund.”

I got on the case and, within days, £948.96 had been credited to Anne’s account. The former school cook, of Coatbridge, said: “This is wonderful. Thank you.”