[SOLVED]820-3787 - Various sensor errors TM0P TP0P TW0P Ta0P

[MUUK]

820-3787

Been previously cleaned (boo!) had backlight issues which have been resolved.

Fan is running full after about 10 seconds into boot.

EFI ASD gives following errors:

TM0P
TP0P
TW0P
Ta0P

Looked at U5870 as this seems to deal with all of these.
Checked continuity to/from this chip checked all resistors which measure fine.

looked clean but Replaced U5870 anyway as thought this would have to be it, but no change.
Checked R5323, R5361 R5360 all measure fine and have continuity.

SMC looks untouched but may try reflow then US unless anyone has any ideas ?

Grateful as always for any help.

 

[dukefawks]

Voltage check on pin 1 of U5870? If ok then probably a SMBUS issue. Check diode mode on SMBUS_SMC_1_S0_SCL and SDA and trace all components on those lines and inspect for corrosion. Last thing would be SMC reflow/reball.

 

[MUUK]

Thank you Duke, that confirmed everything.

Slight variation in diode mode on the SCL / SDA versus a donor pointed me towards SDA.

It was R5360 despite initially measuring ok. Once replaced all working. You may mark as solved Thank you again.