The above error message was reported by running internet hardware test from Apple. A previous question was answered with the fact this was a hard disk sensor error message. On sending the IMAC to Apple service centre in Manila they said it was going to need a main logic board replacement costing approx. $1000 usd. Does this make any sense or are they just incompetent?
OS X Yosemite (10.10.1)
4SNS = sensor error
T = temperature
H = hard disk
That's the breakdown of the error reported, it doesn't mean that they're either incompetent or that it doesn't need a logic board. It' also important to remember that the suite of diagnostic software they use is more comprehensive than the tools they allow us users to have. The only way to diagnose a hardware problem 100% is hands on. If you desire a second opinion is taking it to another repair facility an option?
They have the codes to the tests, we do not. If you don't believe them, take it to another AASP for another diagnostic.
Error message 4SNS/1/40000000:TH00-9.000
