Faulty central locking

The consumer’s issue:

The central locking system on my car wasn’t working when I was using the key. I was charged £100 for the diagnostics to find out what the problem was, and was subsequently informed that the car access system (CAS) unit was faulty. I was quoted over £600 for the repair, so I took it elsewhere where it was cheaper. When they became aware of why I was having the CAS unit replaced, which was after they had carried out the work, they said the CAS unit wasn’t the cause as it has nothing to do with central locking, and instead, the root of the problem was some faulty wiring. I therefore took the car back to the first garage who refused to admit they got it wrong but changed the wire. I want the garage to refund the initial cost of the diagnostic and the repair to the CAS unit, as this was clearly unnecessary.”

The accredited business’ response:

  • We are of the opinion that there were two issues with the car, which is not surprising, considering that it’s 10 years old.
  • We note the comments made by the second garage, but can also see that there was a three-month break between our diagnosis and their work.
  • It was also nearly three months between the CAS unit’s replacement and the second diagnosis of faulty wiring. This meant that there was a total gap of around six months between our first diagnosis and the discovery of the faulty wiring.
  • We carried out the wiring repair free of charge, and don’t think that any further remedy is due to the customer.

The adjudication outcome:

  • The adjudicator did not find that The Motor Ombudsman’s Service and Repair Code had been breached.
  • There was no evidence to suggest that the CAS unit didn’t require replacement, and on looking at the timeline, she felt it was more likely than not that both the CAS unit and the wiring had been faulty, and they were two separate issues.
  • The consumer felt it was very narrow to just consider the timeline, and the case was therefore passed to the ombudsman for a final decision.

The ombudsman’s final decision:

  • The ombudsman agreed with the adjudication outcome.
  • This is because the second garage hadn’t indicated on their invoice that they thought the CAS unit wasn’t faulty or that the accredited business had diagnosed the issue incorrectly.
  • The ombudsman also had no evidence that the CAS unit wasn’t linked to the central locking, and in fact, on researching this, there was evidence that it was.
  • As such, and again taking into consideration the timeline of events, on a balance of probability, it was more likely than not that the CAS unit required replacement and the work should be charged to the consumer.


  • As there was no evidence that the accredited business had breached The Motor Ombudsman’s Service and Repair Code, no award was made to the vehicle owner.