Under a program launched last week, the company will cover repairs for up to two years from the purchase date for iMacs that encounter a video or power problem related to the component glitch. The iMacs in question were sold from September 2004 until June 2005, so until now repairs have been covered by Apple's standard one-year warranty.
"We are initiating an iMac G5 Repair Extension Program for customers whose first-generation iMac G5 exhibit a certain video or power-related issue," Apple said in a statement. "A limited number of iMac G5 computers that were sold between approximately September 2004 and June 2005 are potentially affected."
A company representative would not identify the component in question or say more precisely how many systems may be affected. The computer maker said affected systems have serial numbers starting with numbers in one of four ranges: W8435-W8522, QP435-QP522, CK435-CK522 and YD435-YD522.
Apple has posted details of the program on its Web site.
The company has turned to repair extension programs to cover product issues in the past, notably with an iBook logic board issue that affected some models of the laptop. Another program covers 15-inch PowerBooks that display white spots on their screens.
Those whose iMacs appear to be affected by the issue are encouraged to call an Apple contact center or take their system to an Apple retail store or another Apple authorized service center.