Mazda has begun trials of a system that alerts drivers to oncoming vehicles at junctions or on twistyroads with limited visibility.
The trials, in Hiroshima, Japan, are now focusing on a two-vehicle 'blind collision-avoidance system'.
Road-testing of right-turn and rear-end collision-avoidance systems are scheduled to start later this year.
Mazda has already developed a system that detects vehicles approaching the rear of a car at high-speed, and a pre-crash system that looks for oncoming obstacles and alerts the driver, applying the brakes if necessary.
It is also working on a system that sends information to cars from roadside sensors, warning of potential dangers or hold-ups ahead.