State laws differ but in general the person that did not stop or yield the right of way, against the traffic sign, would normally be found at fault and be responsible thus for the damages the cars received.

The person that was driving without insurance was breaking the law, and hopefully was ticketed by the responding law officer; however that illegal act was not the cause of the accident. It was the person that failed to yield at the yield sign that caused the wreck.

So in most states the person that was uninsured could make a claim against the person that ran the yield sign for their damages. There are some states though that limit the settlement the motorist who was driving without insurance can receive due to their uninsured status.

For example in Louisiana their Insurance Automobile Law is controlled by the "No Pay, No Play" statute, which bars motor vehicle owners who do not have liability insurance from collecting the first ten-thousand dollars of any bodily injury or property damage resulting from an automobile accident. This provision does not apply to passengers in the motor vehicle.

In California they have Proposition 213 which states that uninsured motorist and drunk drivers are not entitled to receive compensation for pain and suffering. This is program is known also known as a no-pay/no-play law. It reduces a person’s right to recovery, for non-economic damages such as pain and suffering, from an auto accident if the driver was uninsured at the time of injury.

To find out if your state has any type of no pay, no play laws in effect, contact your state's insurance regulator.