820-3024 extrem slow and fan runs on highspeed

[boxer]

I have again a strange Macbook Air 11", it turns on but is extremly slow and the fan is going up to max. speed after a 5-10seconds.

No visible liquid damage, tried another battery, harddiscs, all resets and also exchanged the logicboard into a different macbook air. Always same behaviour.

On the apple ASD test I got only 2 errors:

-thunderbolt sleep wake test
-tim test 75percent GB
Pictures are attached!

I have checked especially die CPU temp sensor circuit, all ok. All other voltages are also ok.
Following voltages are going down when the fan is on highspeed, but I assume thats normal due the strange problem:

PPVCORE_S0_CPU_REG down to 0,8 instead 1,25
PPVCORE_S0_AXG_REG 0,45 instead of 1,05
PP1V5_S3_CPU_VCCDQ 0,84 instead of 1,5

Any hint and idea is very appreciated!

 

[dukefawks]

Using a known good battery, must be A1406 type.

 

[boxer]

I tried already a good battery from
another 11" macbook. Same behaviour.

 

[dukefawks]

Was it an A1406 battery?

 

[boxer]

YES! A1406 battery, which works proper in another macbook.

 

[dukefawks]

Any history as to how this happened? Liquid?

 

[boxer]

I dont know any detailed history. But there are no signs of liquid on the board, it looks absolutely clean. I am afraid I have to put that project on hold.

 

[dukefawks]

If you know an Apple service provider let them run MRI/AST on it. ASD misses some sensors sometimes.