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I replaced my MacBook’s fan after running Diagnostics and receiving a PPF003/PPF004 error message. I followed the step-by-step iFixit guide and a few videos and installed it successfully. After the installation, I ran Diagnostics again and received a ADP000 reference code with the message “No issues found”, however, the computer still runs pretty slow. Not as slow as before the fan replacement, but still at a speed that is far from ideal. Other updates I’ve done over the past two years include upgrading the original HDD to a SSD and replacing the SATA cable. What else could I do to increase performance? Thanks in advance!
Ah! I seen this issue too many times! Your HD SATA cable has degraded! I often encounter this issue when I replace the older models HDD’s with a SSD, as Apple used a SATA II (3.0 Gb/s) rated cable. As a matter of practice I always replace the cable when I upgrade these with better SSD’s. Now the Rub! Apple also had a bad run of cables! So outer insulation would flake off and in the 13” models the cases where’t well machined so they tended to sand off the insulation over time. Your Hard Drive Cable Is A Ticking Time Bomb So the first step is to replace the cable! MacBook Pro 13" Unibody (Mid 2012) Hard Drive Cable and here’s the guide MacBook Pro 13" Unibody Mid 2012 Hard Drive Cable Replacement make sure you clean the case surface where the cable sits and place a single strip of electrical tape down (you only need one strip when the larger cable lays). Even still a lot of people damage the cable in the process of putting it in! We don’t want sharp creases where the cable needs to bend around. Folding the cable forcing a tight crease will damage the thin foil wires within it. I use an old BIC pen ink straw (empty) as a forming break to curl the cable around. the radius of the bend should not be smaller than the radius of the straw.
You probably need to install something like Mac’s fan control to get it working properly. Apple is very particular about its fan curve. Sometimes a replacement can ultimately screw up the fan speeds in the OS causing them to run slower as they’re trying not to overheat. The MacOS version should have nothing todo with it you just need to control the fan speeds yourself Via fan speed control app.
