820-00134 - dead, no LEDs

[Palhano]

Device dead, no LED lights up.

I tested with another source and nothing. I have PP12V_S5, but on Q8470 pin 4 (FET_EN_P12V_S5_R) has 10v, so I changed Q8470, but it didn't change pin 4.

I don't have this new component, I removed it from another identical board.

Any tips to find out if the problem is still the Q8470?

 

[2informaticos]

Don't bothr with Q8470 if you get stable 12V_S5_FET voltage.

S5 LED (LE0301) must come on.
If not, check U7600 voltages; you may need to change it.

BTW, did you test removing CMOS cell?

 

[Palhano]

I tested removing the CMOS.

Bad U7600 voltages. I'm going to put only the pins that have voltage.

- 4 - 5v
- 5 - 5v
- 6 - 0.3v
- 7 - 0
- 12 - 4v
- 15 - 4.6v
- 17 - 12v
- 18 - 5v
- 24 - 0.5v

I replaced the U7600 and the problem continues. No LEDs.

 

[2informaticos]

Looks like 3V3_S5 is enabled, so you should have L7610 voltage.
If not, check all components L/Q7610 related.

Did you use "C" version for U7600?

 

[Palhano]

I didn't use it, I didn't have a C version. Do I solve that first?

 

[2informaticos]

You should get the correct chip...