HDD SATA Data Cable with Temperature Sensor for iMac 27-inch A1312 (2009-2011)

Won't your iMac boot, hangs on the Apple logo, or shows a flashing question mark? In the iMac 27-inch A1312 (Late 2009, Mid 2010, Mid 2011) this is almost always a faulty HDD SATA cable. This flex cable combines SATA data, power and the temperature sensor in one — when it fails, the fans also ramp to full speed.

Specifications

• Part: SATA data + power cable with integrated temperature sensor
• Compatible: iMac 27" A1312 (Late 2009 - EMC 2309/2374)
• Compatible: iMac 27" A1312 (Mid 2010 - EMC 2390)
• Compatible: iMac 27" A1312 (Mid 2011 - EMC 2429)
• Connection: SATA II/III, for 3.5" HDD
• Includes HDD temperature sensor (prevents fan runaway)
• OEM part numbers: 593-1296, 922-9862, 922-9861

Symptoms of a faulty HDD cable

• iMac won't boot, hangs on grey screen or Apple logo
• Flashing question mark (no startup disk found)
• HDD appears and disappears in Disk Utility
• Fans run constantly at maximum speed
• SMART errors or slow file access

Installation

🔴 Hard — about 90 minutes. Requires removing the front glass (suction cups), then the LCD panel which is held by double-sided adhesive. Use a heat gun or hair dryer to soften the adhesive, plastic pry cards to gently lift, and T8/T10 Torx for the drive bracket.

Frequently asked questions

Does this cable fit all A1312 years?
Mechanically identical for Late 2009, Mid 2010 and Mid 2011, but the sensor connector can vary slightly between years. Check the OEM number on your old cable to be sure.

Why are the fans at full speed?
Without a valid signal from the HDD temperature sensor, the SMC defaults the fans to maximum as a safety measure. A new cable with working sensor solves this immediately.

Can I use an SSD with a separate sensor instead?
Yes, but you still need a working SATA cable. Software like Macs Fan Control also helps, but a good cable is always the cleanest fix.