[SOLVED]820-2879 no green light

[wirelessplanet]

wasn't really liquid damage but had a bit of corrsion on u7000. took it off and cleaned it.

u6901 pin 5 only has .5v
q7035 gets really hot as well.

 

[dukefawks]

At least U7000, Q7030/35 should be replaced. Check R7005, R7021/22/51/52 and traces to them. Maybe before you do anything check resistance to GND on PP3V42, if under 15K then MCP is probably also dead.

 

[wirelessplanet]

changed u700 q7030/35. still same issue. all the resistors traces are good.

 

[dukefawks]

What same issue, I doubt Q7035 is still getting hot. What is PPBUS and 3V42 voltages?

 

[wirelessplanet]

q7035 isnt getting hot anymore, but still .52v on 3v42

where should i measure ppbus?

 

[dukefawks]

3V42 is the first thing you need. Is there a short on 3V42? Resistance to GND on 3V42?

 

[wirelessplanet]

no short on 3v42

res to ground is when you put red lead on ground pin and com lead on 3v42 right? that reading is 9.28k

 

[dukefawks]

Voltage on C6990? Corrosion in U6990 area?

 

[wirelessplanet]

c6990 - .557v
no corrosion on u6990 area. i can replace it though if you think i should.

 

[wirelessplanet]

I had a feeling my multimeter was giving out (was giving me weird readings on an iphone 6 i was testing) I just went and bought a new fluke multimeter and read 3v42 and am getting 1.19v on pin 5 (u6901)
c6990 - 2.65v

 

[dukefawks]

R6905 checked?

 

[wirelessplanet]

r6905 - 1.48 k ohm

 

[dukefawks]

Yes, you gave the answer, I assume you can figure this out. Engage the brain.

 

[wirelessplanet]

yup
thanks for the help of fixing my first one wire