Hard drive cable for Kingston SSD

It sounds like you have two different issues here:

• Bad HD SATA cable
• Incorrect drive for your system

OK lets hit the cable problem you are facing first. Here's the IFIXIT guide: MacBook Pro 13" Unibody Mid 2009 Hard Drive Cable Replacement you'll need to follow to replace it, and here is the correct part you'll need: MacBook Pro 13" Unibody (Mid 2009/Mid 2010) Hard Drive Cable - Apple P/N 922-9062. The cable you currently have is the original version of the cable over time Apple has improved it. The 922-9062 is the better cable.

The next issue you're facing here is the given SSD you are trying to use may not work in this system. Your system has a SATA II (3.0 Gb/s) interface. Not all SSD's will work at this SATA speed. You'll need to review the spec sheet of the SSD unit to see if its compatible. As an example here is the Samsung 750 EVO spec sheet. Check out the Interface line thats what you want to see on your SSD. You may need to contact Kingston to get the spec sheet as some of their spec sheets are not online.

Last thing here is making sure your systems firmware is up to date. Follow this Apple T/N: About EFI and SMC firmware updates for Intel-based Mac computers make sure yours is at this level or newer.