Chosen Solution
Hi Guys, My MBP ran without any issue until 2014 mid and then it started to make fan noise(running at 6200rpm), and fans were always running. Then it started to give charging issues. When I plugged my charger in it quickly blinks amber and then goes out and will not charge the battery. But some times it charged the battery. Now Machine is very slow and kernel task is always over 100%. When I ran AHT it gave 4SNS/1/40000000 TsOP–124 error. And TG pro shows all the sensors in working condition, but PalmRest sensor is not showing in the list even. I am helpless at this stage and here I don’t have apple stores to repair this. Apple reseller in here telling me to replace the logic board without inspecting this issue deeply. I want to find whether a failed thermal sensor cause this problem and if it is, which one is the failed one(Palmrest/Optical drives/Power bus). Thanks Update Hi Dan, I de-assemble my MBP to check that upper case keyboard ribbon cable and found this. One of the Capacitor or Resister(I can not identify the item) is burnt, is it relevant to this issue. Please give a look and advice me.
Here’s a good article on how to interpret AHT: How to invoke and interpret the Apple hardware tests. You are correct your error 4SNS/1/40000000 TsOP–124 does imply the palm rest thermal sensor. Did you spill anything into the keyboard or track pad? If you did it sounds like you have some corrosion on the keyboard flex circuit where the sensor is located. Here’s the IFIXIT guide to get to the ribbon cable: MacBook Pro 13" Unibody Late 2011 Upper Case Replacement. As you can see its quite a bit of work to even get to it. You may want to conceder getting a replacement upper case.
That cap is not causing the sensor issue, the liquid damage to the trackpad is. Replace, and clean the board in 99% alcohol and a baking tray from the corner store for $1. Find a dead board for $30 or so online to steal parts from that is the same 820-2936 that yours is. That cap, while not being good that it is blown, is not going to be the start all end all of whether your laptop works or not. Liquid damage elsewhere is causing the charging issue.
