Hi, i just buy P28-G01 1720 board, try to test it on EG9 car, but there smoke came out from ecu. After open it look like R75 and R77 burn. There also burn track on back side. Referring on old H-T thread R77 = 6.6Ohm and R75 = 1.7kOhm. but i cannot get any 6.6Ohm resistor, it is ok if i replace it with 7.6ohm resistor?

 

Here some picture ,A13 ----goto---> R75 & R77 and where R75 and R77 other side point go? connect together?

 

They go to Q36 R76-----then to A23 PG1.

>[A13]-----{R75}-------{R76}--------{Q36} (3rd post)
>[A13]-----{R75}-------{R77}--------{Q36} (2nd post)
--------------------------------------{Q36} (1st post)-----[A23] (PG1-ground)

My eyes started to get tired. so this is where I left off...

 

Dont put the ecu back in the car after you repair it. The car obviously has something wrong with the wiring if it fried the ecu.

 

Thanks GhostAccord for the answer, complete replace it. Test on lude without chipping got CEL.

P/s: Good rest GhostAcord, thanks and zzZz

 

Hm i got test with lude it ok, no heat resistor or esle, EG9 used P30-000 it obd1 and this also obd1 why it really happen burning up the resistor?

 

I had that same problem
what does that part of the board control ?

 

As you see R77 go to A13 on ecu connector, it go to MIL (Check engine light) if i not wrong.

 

my head hurts from readin your post's, what exactly are these resistors and what do they control? what is he trying to fix? got the same problem with one of my ecu's

 

It check engine light control..after tracking the circuit, last point is under OKI Chip M82c55a-2 refer my attachment. i dont know where it go after that.

 

Sure it didnt collect any condensation or get wet somehow???