Apparently, I have changed my I/o board my ooutput speaker it's working fine but battery still not charging, fan still on high speed and system still slow. So I was recommended to change the fan but I have no idea what to do about the battery and system speed. Any suggestions pls?

I have found the culprit causing my fan to run on high speed continuously. Apparently I changed the battery a while ago and the technician installed a cheap fake battery which was causing my system to misbehave. I have changed the battery and Mac is back to working perfectly fine now.

Adamant IT Hello, thank you very much for replying. Install on my mac software that controls fan revolutions. The software shows cpu core temperature 2 and 3, airport, battery, and other values. The CPUs show values ​​of 39 to 44 degrees. Does that mean that the back-up sensors are working well? Another flaw that I have located is that the USB port that is located in the charging circuit does not work. The operating system says that you remove the device because it consumes a lot of power. Excuse me asking you so much. I appreciate your opinion.

Thanks, found some, just have to figure it out how to use them now ;)

Apple Service Diagnostics. You need to do a lot of digging to find them, and there's specific versions for specific macs. They're not very relevant these days because there's no ASD for anything 2014 onwards.

Have j fix it? I have same Mac and issue

Yea the DC-in board has the audio circuit on it as well, you were in the right place 👍

@@Adamant_IT Thank you; much appreciated. Also, any recommendations for a supplier that will provide a reliable/quality part. My web search runs the price gamut from $7 - $80 Dollars US. Thanks again!

where to download the test tool?My Macbook Pro 2012 mid also got this problem

Apple Service Diagnostics. They're not available to non apple techs, but if you look hard enough on the internet, they're out there.

Stockholms Oskar could you please send me the link to the correct board I need for my mid 2013 MacBook Air? Thanks.

Thanks for the reply, I ended up going to Apple and they said that the sensor was bad, as well as a view other things.

Hi VisualLife I have got exactly the same problem: fan works full speed, system slow, facetime not working, (says due to high temp) but zoom works, temperature normal. I can slow down the fan, but the system still very slow, any recommendations?

Is it buzzing/rattling, or just running at high speed? If it's a buzz/rattle, the fan bearing has gone, and you can buy a new fan from ebay. If it's at high-speed, it's a sensor issue and you need to get hold of Apple Service Diagnostics to figure out which sensor has died.

@@Adamant_IT It is running at high speed...oh dear, so i cannot change the fan myself to save money if it is a sensor issue as there is no way to buy spare sensor chip...

Ah that's a Retina model, right? I think there's a way of figuring out thermal sensors on the Retinas, but I don't know how to do it I'm afraid!

It happens randomly, with no heavy workload, and no high temperature. I suddenly hear the fan running loudly, but the Macs Fan Control app shows that the fan is running very low, like 860, and stuck at that number. It is like the fan sensor goes numb sometimes. That's when I change the sensor from Automatic to CPU PECI for 2 seconds. The fan then rises at like 3500, and comes down to the usual 1200. As if I was waking the sensor up. If I don't do anything and let the fan run loudly, it just doesn't stop. It can take a long while before it finally goes back to "normal". I usually don't have the patience to wait... I mostly browse the web or work in a text document. Nothing heavy. It can happen when I just open a web browser or any software, or while I'm working. Apple Mail is always open in the background. Checking the Monitor Activities, there's no high CPU or memory usage. Before that, I had a 2012 MacBook Air, and never had a problem with the fan. *edit for precisions.

Adamant IT , Hello Brother! I found it the DCN board. Then, I have question for you. If I change the board, Need I some program for the installation of board? Can I replacement hardware and turn on without a programa? I hope you can understand😬

Adamant IT thanks brotha! You are very interested with others! Thank you so much! 🤝

Sadly not. The modern macs (retina onwards) only use in-house tools with Apple, which to my knowledge can't be downloaded.

@@Adamant_IT Thanks for responding. I have a situation with a Macbook air a1466. The fan spin high speed 6450 rpm constantly. I found out the signal SMC_FAN_0_CTL measuring in TP idles normally but when I measure the same signal coming from SMC to mosfet Q6060' source the voltage is 3.6v - this is the 3v coil - do not idle and in Drain voltage is 5.15v which is FAN_RT_PWM. At this voltage the fan spin at his maximum voltage. Any suspicion?

Adamant IT thank you so much for your reply - it’s great to have good people like you out there! I got the photos and they show a bit of corrosion on the cable, plus three of the indicators have been triggered. I found it especially strange that it took them 15 days to discover the damage. I’ll try to fight them, but if I don’t get anywhere with that I’ll take it somewhere else and try getting the cable replaced instead. Thank you so much again!

@@Adamant_IT Thanks for that, I'll give them a try and if I remember I'll let u know.....thanks! :)