Recent content by BMarden

Yes, ALL_SYS_PWRGD is 3.2V for 320ms, pulse shows very clean on scope.

No liquid damage. No CPU VCore PP5V_S0 and PP1V05_SO are at 5V and 1.05V respectively, but also intermittant (about 250ms on and 3 sec off)

I have an 820-2936 with Intermittant Fan Spin (no Liquid Damage) PP3V42 - 3.47V PPBUS_G3H -12.58 V PP5V_S5 - 5.0 V PP3V3_S5 - 3.3V PP5V_S3 - 5V then off, 5V then off PP3V3_S3 - 3.3V then off, 3.3V then off I tried new clock chip, same result. Any ideas? Thanks

I have been hearing of more and more issues with Macbook Pro 13 2012/13 and random trackpad movements, tried cleaning and PRAM reset, no luck. Has anyone heard of this being HW level issue? No liquid damage to my knowledge. Thanks

Sense circuits look good bottom R7051 R7052 is 3.4Ohm, from R7021 to R7022 is 21 ohm. I was measuring around PPBUS MOSFETS and magically PPBUS_G3H went to 12.68, so I hit all the points I was measuring with solder and Re&Re the ISL6259 All is good now ASD passed Thanks

Liquid Damaged 820-2936 no green light, no fan spin. I cleaned up corrosion around ISL6259 , LCDS connector, U5400 and Q5300, Q4262 was corroded and replaced from donor board, a few misc caps and resistors replaced due to corrosion (mostly around U5400 and Q5300). Plugged back in and got Green...

that's a bummer

My bad, PCH... I assume the video signals are generated by the PCH and the T29 is only Driver circuits? Is that correct?

I checked external, same deal, same flicker. The machine came from another shop, I don't think this original logic board for case as no liquid evidence on logic board, normal grime and dust so it hasn't been cleaned either. I suppose a careful reflow of MCP couldn't hurt at this point.

if R5280 is normal, Bat connector looks clean, BIL change has not effect, and PPV3V42 is present... I would try replacing D6950, Zenor's can be a bit funny

Hi Duke, I am curious. How are there pulses on PP5V_S3? Would they not get filtered by C7290, 91, 93? Would the pulse freq. be the 300KHz PWM freq? Thanks

I had a look at PP1V05_S5 on scope, it measures 1.06 and it looks like there is about 10mV of 300KHz ripple on it. I also checked PP3V3, it has no detectable ripple. Not sure if thats normal or not. Not sure if anything else I can check, or just call it bad GPU and turn it into a donor. Any...

I would clean up obvious corrosion, and remove L7220 to prevent further damage. Check Q7220 for Drain to Ground Short (Pin 2 - 3), but I am just learning so take it with a grain of salt.

FYI - Just for shits and giggles I did an SMC reflow and BAM, works perfectly.

I have 220-2936, bongs, boots, charges, green light etc, all good. The video flickers a couple time on initial boot and when in full screen video, since its Intel HD (not ATI or NVidia) I'd like to think it may be power instability rather than GPU issue. I replaced C167D and C167E on PP1V05_S0...