A woman whose Mercedes was written off has lost a $73,000 insurance dispute after the Australian Financial Complaints Authority (AFCA) ruled there was an opportunity to stage the accident.

RACQ had declined the claim, saying it was fraudulent.

The woman, who held a comprehensive insurance policy for a 2010 Mercedes Benz E63 sedan with an agreed value of $73,000, says she was driving through a roundabout towards K-Mart at about 6pm when a vehicle she had not seen crashed into her passenger side.

There were no witnesses to the incident, no CCTV footage and the police were not called.

The next day, she lodged the insurance claim but AFCA ruled RACQ was entitled to refuse payment as it was “not persuaded” the car damage was unintended and unexpected, which the policy conditions required. AFCA also said the car's true value was likely to be close to $50,000.

“There was an opportunity to stage the accident and there is a potential financial windfall of almost $23,000 if the claim was paid,” AFCA said.

The woman admitted her husband had reduced the odometer on the Mercedes, indicating it had travelled more kilometres than recorded, affecting its value.

RACQ arranged for the two vehicles to be forensically examined, and the investigation found the Mercedes was stationary with the ignition likely turned off as the passenger side curtain airbags were not deployed. Crash data showed the driver of the other car applied the accelerator 0.41 seconds before the collision to reach a speed of 44 kilometres an hour at impact.

AFCA said the forensic evidence was "compelling" and the report highlighted issues with the woman’s conduct. It raised “significant inconsistencies” with the woman’s description of the accident and established the other car had sufficient opportunity to avoid a collision.

“This cannot be reconciled with her evidence or the proposition that the collision was unintended or unexpected,” the ruling says.

Click here for the full ruling.