-
For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.Subscribe Now
820-01598 no gong
- Thread starter MarcinRdm
- Start date
Yes, try voltage injection method.
Strange situation. R7744 was getting hot. I removed it. The short circuit was still present. Later, U7710 started to heat up, so I removed it and again the short circuit did not stop. Now the U8110 is heating up. Should I remove it ? This is the first time I have this situation.
You have 2.2 ohm resistors in series with U7710 and U8110.
Comparing resistance to ground (ohm scale) on both sides of these resistors can tell you where is the short coming from.
Seems that overvoltage occured on the 5V_G3S power rail and affected more circuits.
Comparing resistance to ground (ohm scale) on both sides of these resistors can tell you where is the short coming from.
Seems that overvoltage occured on the 5V_G3S power rail and affected more circuits.
Do you get USB activity?
Tested external video?
Tested external video?
Missing both image and backlight?
Do you get 3V3/5V_S0SW_LCD?
DP_INT_HPD should go high at same time.
Did you test with known good LCD assembly?
Do you get 3V3/5V_S0SW_LCD?
DP_INT_HPD should go high at same time.
Did you test with known good LCD assembly?
"PP5V_S0SW_LCD 1.4V"
That's your problem; T-CON backlight circuitry requires 5V.
Check U8500 voltages.
That's your problem; T-CON backlight circuitry requires 5V.
Check U8500 voltages.
You probably need to replace U8500.
First, check diode mode to ground at 5V_S0SW_LCD, w/ and w/o LCD connected.
"4 - 1.3v
5 - 0v"
In previous post, you've said to have 1.4V at pin 5.
And pin 4 is not used...
First, check diode mode to ground at 5V_S0SW_LCD, w/ and w/o LCD connected.
"4 - 1.3v
5 - 0v"
In previous post, you've said to have 1.4V at pin 5.
And pin 4 is not used...
Yes, you can test with A1706/7/8, or other T2 LCD assembly.
I just looked at A1708 schematic and may not be the same option for backlight test.
It should give image, but not sure about backlight.
Be sure all R8450-3 are good.
Post BKLT_EN_R and BKLT_SD levels.
Check voltage and diode mode on SCL/SDA lines.
It should give image, but not sure about backlight.
Be sure all R8450-3 are good.
Post BKLT_EN_R and BKLT_SD levels.
Check voltage and diode mode on SCL/SDA lines.