The National Highway Traffic Safety Administration (NHTSA) is looking into possible defects with 2004-2009 Toyota Prius steering shafts.
No official recall has yet been announced, and will only follow if the NHTSA grants a defect petition claiming the steering column linkage was improperly assembled.
According to The Detroit News, a possible 561,000 Prius models from 2004-2009 model years would be affected.
The NHTSA's latest investigation (action number DP13001) follows a petition from Virginia-based Automotive Systems Analysis, who discovered wear and corrosion at the base of the steering column during inspection of a San Diego client's 2005 Prius.
Automotive Systems Analysis reports "that no known service took place that would account for this condition since the time of vehicle production."
If a recall is issued, it would be the second recall for a Prius steering issue in four months. Back in November, Prius models built between July 2003 and April 2009 were recalled due to steering response problems, along with thousands of Toyota Corolla models.
Back in 2006, 170,000 2004-2006 Prius were recalled for another steering issue, where an intermediate shaft was liable to cracking.
We'll bring you more details on the latest investigation if and when a recall is announced.