Update . managed to find and run ASD 3S157 (OS +EFI) whilst connected to an external TV.
Ran the ‘Sensors’ test alone and the ‘SMC’ test alone as these are the two areas which flagged up errors.
EFI test results showed 2 errors
[image|2009931]
[image|2009929]
OS test results showed 13 sensor errors in total
[image|2009933]
[image|2009932]
With the 2 options (sensors + smc) unchecked. All other tests including , memory , processor and video for example passed.
So from my understanding, the SMC chip monitors all sensors on the logic board, which explains immediate error detection at the start of the EFI + OS tests. And the stand alone ‘sensor’ test revealed the extent of the sensor errors , around 13.
The iMac was assembled , faulty LCD all connected etc at the time of the test.
From my understanding, can one faulty sensor on the main logic board create other sensors to be faulty? Or are they all monitored individually by the SMC?
Logic board or LCD display at fault ir both?