MacBook Pro 15" Core 2 Duo Model A1211 Hard Drive Replacement
The default position of the sleep light and IR sensor connector assembly is directly over the hard drive breather hole on many replacement hard drives, including Hitachi Travelstar 7K500 and 5K250 models. Other brands also have breather holes in similar places. Be careful not to cover the hole with the adhesive portion of the connector tape, as this can interfere with proper operation of the drive. I was able to reinstall the cable twisted at a slight angle in order to keep the hole open.