Between ground and output measures 0.828K ohms and ground to input measures 51.8k ohms.
-
-
On the pcb where do I put the red and black wires to inject voltage with a power supply?Comment
-
You need a bench power supply with adjustable voltage and current. You just can’t put “some” PSU on it and plug it in.Comment
-
I have an adjustable power supply also I have removed and measured the two 514 resistors and they measure at 0.510milliohms, is this what it should be or are they bad please?Comment
-
Also, when measuring both pads when they beep both sides this is the readings I get in the picture.Attached FilesComment
-
-
- First, what's the resistance between the 12V line and ground?
- Second, is the 12V line connected to the point where you measured 3.1 ohms? (continuous beep)
- Third, if the resistance between the 12V line and ground is low, inject 1 or 2V into the 12V line and monitor the current draw.
If it draws more than 1A, the shorted component will heat up within seconds...
If the current draw is low at 1 or 2V, gradually increase the voltage until it reaches 1 or 1.5A.
Attached FilesComment
-
The resistance between 12v line and ground is 2.4ohms and yes the 12v line is connected to the point where I measured 3.1ohms, also while injecting voltage could I use IPA on the pcb to spot the component that gets hot as I don’t have a thermal camera or electrical frosting spray.Comment
-
Thank you, I have soldered the black wire to ground and red wire to 12v but when I checked for continuity to make sure they were soldered on properly both the ground and 12v get continuity through the black wire, is this how it should be or should the 12v be getting continuity through the red wire as the red wire is the one going to the 12v?Attached FilesComment
-
-
what is U3 ?Comment
-
I unplugged the connector that leads from the board in the picture attached to the board that had the short to ground and now the short to ground has gone so I assume that it’s an issue with the board in the picture attached but where should I look or test on this board?Attached FilesComment
-
-
Hi,
I have an iMac with the power supply reference: ADP-200DFB.
This power supply is not working and when trying to debug the problem with a multimeter, I found what I thought to be a short circuited diode (the short-circuit is to ground).
With the continuity test it beeps both ways, so doesn't block current flow at all then reverse biased. But after removing the diode the beep continues and the diode seems healthy. It seems to exist a real short-circuit.
As I have another ADP-200DFB power supply (faulty one as well), I have checked the same... -
Hi All.
I have an 820-02016 board (A2337 M1) that has come in for data recovery. Reported as liquid damage, but no visible evidence of any liquid damage.
Board was initially stuck at 5v, and current only spiking occasionally to around 400mA and cycling.
After initial troubleshooting, found that C7800 (which feeds the power rail PP5V_BSTLQ_VOUT_SPMU) was dead short to ground.
Replaced C7800 and short gone. Board still stuck at 5v. Current draw behaviour changed. It now spikes up for a second to around 100mA to 130mA, then drops down to... -
Hi everyone,
I'm having a serious issue with my ASUS Zephyrus GA401I (4 years old, worked perfectly until recently). The system is lagging heavily, even in the BIOS, and is charging extremely slowly (a few percent in hours), making it nearly unusable. I suspect a motherboard or power delivery issue.
Symptoms:- Severe lag across the system, including BIOS navigation.
- Slow boot times and unresponsive performance in Windows.
- Battery charges very slowly (e.g., ~5% in 2–3 hours).
- No error messages or BSODs, just extreme sluggishness.
What I've Tried:- Replaced
-
Hi everyone,
I'm having an issue with my Lenovo ThinkPad P43s. The laptop does not power on when the internal battery is connected, but it works fine on AC power alone (battery disconnected). Once the battery is reconnected, the system becomes completely unresponsive — no lights, no fan spin, nothing.
Here's what I've tried so far:- Power/EC reset (held power button for 60 seconds with battery and AC disconnected)
- Booted successfully on AC power only with the battery disconnected
- Visual inspection of the battery — no swelling, burn marks, or connector damage
- Battery
Comment