Beginner question - Hot RT9513 chip

[mon2]

Let me post the G4 BV in the schematic section.

Posted here:

HP G6-1241sa - DA0R13MB6E0 REV E - Boardview - Badcaps

While I go and cut the grass / weeds, review the soldering of this IC. Review the resistance to ground of the inductors as per our posts and use the BV to locate the linked inductors. If there is a shorted part on the rail, this part can heat up but it really should have turned OFF to prevent this situation.

[Darren Hibbert]

Are you sure the chip is RT9513?

See your other thread here:

What is this chip? EQ ED B1Y - Badcaps

Update:

Study the G4 schematic and review PU3 = RT8223.

This dual regulator creates the +3VS5 and the +5VS5 rails.

With no power to the board, measure the resistance to ground of PL20 inductor (either side is ok).
With no power to the board, measure the resistance to ground of PL23 inductor (either side is ok).

Post each measurement.

Does your board like the one below?

PL20 = 3.0 ohms
PL23 = 0.4 ohms

[Darren Hibbert]

PU3 chip

Resistance to ground -

Pin 1 = 110.5K
Pin 2 = 6.08K
Pin 3 = 110.4K
Pin 4 = 4.07K
Pin 5 = 4.07K
Pin 6 = 130.6K

Pin 7 = 0.5
Pin 8 = 1.3
Pin 9 = O.L
Pin 10 = 2.3
Pin 11 = 0004
Pin 12 = 6.2M

Pin 13 = O.L
Pin 14 = 0002
Pin 15 = 0001
Pin 16 = 0.9M
Pin 17 = 327K
Pin 18 = 13.9M

Pin 19 = 6.14M
Pin 20 = 3.1
Pin 21 = 6.1
Pin 22 = O.L
Pin 23 = 9.93K
Pin 24 = 3.2

Hope this means something to you as it means zilch to me!!!!

[Darren Hibbert]

[mon2]

We are hunting for shorted output rails and you appear to have a few:

Pin 11 = 0004
Pin 20 = 3.1
Pin 21 = 6.1

Remove all power. Meter in resistance mode.

Measure the resistance across the mosfet pins for the following parts:

PQ51
PQ46 ; low side mosfet
PQ26
PQ21 ; low side mosfet

Measure:

source (1-2-3) & drain (5-6-7-8) ; pick any of the pins from the shared pins
source (1-2-3) & gate (4)
drain (4) & drain (5-6-7-8)

Post each measurement. We are hunting for a shorted mosfet which will probably be on the low side (the mosfet that goes to ground for each leg).

Do not power up during these tests. From the shared low resistance measurements, both rails are shorting.

[Darren Hibbert]

PQ51 - Source & Drain = 5.6M and dropping
Source & Gate = 001.5
Drain & Drain = 3.800M

PQ46 - Source & Drain = 003.1
Source & Gate = 2.500M
Drain & Drain = 2.500M

PQ26 - Source & Drain = 2.500M
Source & Gate = 001.0
Drain & Drain = 3.200M

PQ21 - Source & Drain = 000.4
Source & Gate = 6.30M
Drain & Drain = 6.30M

[mon2]

You are missing a few units of measurement in the posted values.

Flux and remove PQ21 off the board. Do not power up without these parts.

Measure the resistance to ground again with pq21 on the board.

Also concerned about PQ46 but need to know the units of measurement.

[mcplslg123]

Remove the chip PU3 and then measure resistance to GND again on coil PL20/23. Next measure resistance to GND on pin8/17/16 of PU3(pcb pads).

PS:DONT PUT POWER WHILE PU3 IS NOT SOLDERED.