"During a high-speed spin test of the rotors on Friday, the command sequence controlling the test ended early due to a 'watchdog' timer expiration," NASA said in a statement on Saturday.
"This occurred as it was trying to transition the flight computer from 'Pre-Flight' to 'Flight' mode. The helicopter is safe and healthy and communicated its full telemetry set to Earth," the US space agency said.
The watchdog timer oversees the command sequence and alerts the system to any potential issues.
It helps the system stay safe by not proceeding if an issue is observed and worked as planned.
The helicopter team is reviewing telemetry to diagnose and understand the issue, following which they will reschedule the full-speed test, NASA said.
The Mars Helicopter, Ingenuity, is a technology demonstration to test powered flight on another world for the first time. It hitched a ride to Mars on the Perseverance rover, which made a February 18 touch down on the Red Planet.
Once the rover reaches a suitable "helipad" location, it will release Ingenuity to perform a series of test flights over a 30-Martian-day experimental window.
For the first flight, the helicopter will take off a few feet from the ground, hover in the air for about 20 to 30 seconds, and land.
That will be a major milestone: The very first powered flight in the extremely thin atmosphere of Mars.
After that, the team will attempt additional experimental flights of incrementally farther distance and greater altitude. After the helicopter completes its technology demonstration, Perseverance will continue its scientific mission, NASA said.