Chosen Solution

Hey there! My 3,5 year old MacBook (OSX 10.9.1) stopped working last week. After watching some videos on youtube the screen just turned gray and all I could do was to force it to shut down. When I start the device now the screen shows briefly the Apple Logo and then I get the same gray screen. I tried SMC and PRAM reset, booting in save and recovery mode etc. but I can’t launch the OS. All I get is a gray screen. (in save mode it is black) Only the hardware test worked. It showed this error code after the test: 4SNS/1/C0000008: TsOP–124 After some research I found out, that this refers to a faulty temperature sensor. So I have 2 questions: Can you tell which sensor it is and if I can replace or fix it, OR disable it in software? Could it be, that the problem is not caused by the faulty heat sensor but something else? Because from what I have read so far, faulty heat sensors usually cause high fan speeds and no gray start screen. PS: sorry for bad grammar or misspellings, english is not my mother tongue.

Here’s a good writeup on how to decode Apple Hardware Test error codes: CNET - How to invoke and interpret the Apple hardware tests Looking at your error: 4SNS/1/C0000008: TsOP–124 4SNS: System sensor T: Temperature s: Palm rests for laptops O: Optical drives P: Power bus You have a few sensors firing off here ;-{ Lets see if you can isolate this down a bit. Lets try restarting under Safe Boot mode. Follow this Apple TN" OS X: What is Safe Boot, Safe Mode?. Does the system appear to run longer without into a grey screen? If it does from another Mac system download this Temperature Gauge Pro and copy it over to your system and install it. It should help show you what your sensors are telling you. You may need to stick your system into a tight plastic bag (taking as much air out as possible) in your refrigerator for a few hours (not to long and don’t freeze it!). I suspect your heat sink has failed. The clue will be seeing all of the heat sensors running high and your fans running at full speed. Paste in a screen shot or two so we can see the sensors of Temperature Gauge Pro. Update OK, the screen shot of Temperature Gauge shows the fans are not working at all. Thats not good. Do you hear them? If you do the sensor on the fan units are not registering within SMC. So the SMC is not controlling them. The screen shot of the display shows us the GPU is failing likely from the heat if the fans are not working correctly. The function of cooling the system was to buy some time if the system didn’t run very long. At this point I don’t think it offers anything useful. You stated you got the system back from service what did they do? And what was the reason you brought it in? Update Just to be clear here, a defective temp sensor would not cause your display to react like it has. Looking at Temperature Gauge shows us all of the temp sensors are working! So there is nothing here to replace on the sensors them selves. The only sensor that appears not working is the tach’s for the fans, they don’t appear to be running high enough (better than 2k RPM) given the heat levels. If they are working and the screen shot is not telling me correctly then the GPU chip is failing here. You’ll need to get the full version so you can track the temp & fan condition when the screen goes on you to verify this. So far I don’t see replacing the heat sink (or redoing the thermal paste) is the answer until we can deal with the fan issue. You are sure the system has not gotten wet some how? Correct If the fans do ramp up as the system gets warmer and the temp of the GPU does not go red line then the GPU chip it’s self has a problem. It could be a cold solder joint or a defective chip. Other than swapping out the logic board there is not much one can do here with a BGA chip setup with out the proper gear. You may want to get your system to a Apple Store as they check to see if there was a recall for this unit and they often offer a cheaper price for logic board swap outs.

I have the same problem but updating the BIOS didnt work. Please help me, as my fan runs automatically always and 90B error is displayed always at startup, from the very first day I bought HP Probook 4430s. Even the vents are clean and I regularly clean them. Still it shows the same error. I have also replaced the fan but still it shows the same error. Please suggest me what can be the reason and what can be a possible solution.

I have had the same issues along with a few others with my 15’ Early 2011 MacBook Pro. Check out this website. https://mbp2011.org/