New report from the USA AAA has found complex sensors can add up to US$3000 to repair bills in minor accidents.

Modern cars are safer than ever before, but the complex sensors and cameras required to make features like autonomous emergency braking and lane-keeping assist work can be seriously costly to fix.

That's according to a new report from the North American AAA, which found minor accidents damaging only the bumpers, door mirrors or windscreen can cost up to US$3000 ($4200) more when semi-autonomous technology is involved.

The study was conducted on three top-selling models from popular vehicle categories in North America. Small SUVs, medium sedans and full-size pickups were all used for the sturdy, which then considered the cost of original manufacturer components at list price to inform the result.

“Advanced safety systems are much more common today, with many coming as standard equipment, even on base models,” said John Nielsen, AAA managing director of automotive engineering and repair.

“It’s critical that drivers understand what technology their vehicle has, how it performs and how much it could cost to repair should something happen.”

According to the AAA, the front radar sensors used for autonomous emergency braking and adaptive cruise control can cost between US$900 and $1300 ($1250 and $1800) to replace, while the rear radar can set you back up to US$2050 ($2900). Mirrors with lane-keeping hardware are worth up to US$1100 ($1550), while parking sensors could cost US$1300 ($1830).

Even windscreen damage, common from stone chips, can be a seriously expensive exercise – and one with safety consequences, if the damage obscures a camera or sensor.

“It is not unusual for windshields to get chipped or cracked, especially for drivers who commute on a daily basis,” Nielsen said. “This may be an eyesore on a regular car, but when it falls in the line of sight of a camera or the driver, it becomes a safety issue that needs immediate attention by a facility qualified to work on these systems.”