HP 450 G2 Shorted

[Jesse James]

Hi I have a board that is shorted and need some help. When plugged in power light and caps light always on. I have traced it down to an area where 3.3v is shorted but need to find the source of short. The 19v and 5v look ok.I have uploaded schematics and pg 47 PU301 pin 9 shorted as well as PL303 PC314 and PJP303. Some guidance would be helpful

Board LA-B181P
Rev: 1.0

[Techtiger]

Re: HP 450 G2 Shorted

Left one Pad of PL303 & put your multimeter in diode mood and test both sides of the Coil for value or else remove PJP303 JUMPER With the help of soldiering iron and test Diode mood for value both sides
If the short is on +3VDSP side those Fets PQ301/PQ303 might be your case if not you have to test all components with that line 7caps & 1 Resistor

[Jesse James]

Re: HP 450 G2 Shorted

I removed PJP303 jumper and short is on 3vds side. I will post back when I find more

[razu]

Re: HP 450 G2 Shorted

Remove 3.3volt coil and Inject 3.3v by lab psu.......then u look the meter of psu.........

[ktmmotocross]

Re: HP 450 G2 Shorted

I removed PJP303 jumper and short is on 3vds side. I will post back when I find more

tahat rail is main rail for aics for all over the board , so inject 3V with current 2A and find burning component