[SOLVED]820-3115 - no green/orange light.

gcain

New member
Works fine off a charged battery. Missing PP3v3_s4 and then PP5v_S3.

C7800::1 = 2.5v
C7800::2 = 0.480v.


Q7803::1 = 0v
Q7803::3 = 3.24

Q7803::1 signal comes from U7970::4 which seems to be 0.0v

Any suggestions on where to look next?
 

TCRScircuit

Super Moderator
Staff member
If it works of a charged battery 3v3_s4 and 5v_s3 is irrelevant. Why are you checking 3.3 and 5v rails when you don't have a green light?

Let's start from the beginning.. History? Why is this in your shop? Liquid? If so where?

Voltage on PPBUS_G3H?

SMC_BC_ACOK voltage?

Look at the schematic at U6901 and U6900 and see if they are doing their job.
 

gcain

New member
If it works of a charged battery 3v3_s4 and 5v_s3 is irrelevant. Why are you checking 3.3 and 5v rails when you don't have a green light?

Let's start from the beginning.. History? Why is this in your shop? Liquid? If so where?

Voltage on PPBUS_G3H?

SMC_BC_ACOK voltage?

Look at the schematic at U6901 and U6900 and see if they are doing their job.

Thanks TCRS, I've been focusing on programming this year and have forgotten the thought process for some reason.

PPBus = 12.59v
SMC_BC_ACOK = 3.490v
U6901 has 3v42_G3H and 3.4v on ::1 and ::2

U6900::1 = 3.4v
::4 = 3.4v
::5 = 15.879v
 

gcain

New member
Actually, mark this one solved.

When I saw the above measurements I swapped the DC Board and it worked fine.

Thanks again TCRS.
 
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