No Power : Acer Swift 7 Pro (Board model ZDL)
Problem : When plugged into power the laptop shows no signs of life but a small periodic tick noise, no battery charging indicator.
Observations :
- The laptop makes a tick sound at regular intervals when plugged in via the charger.
- The laptop negociates with the Power Delivery charger to 20V as expected but shuts back down to 0 then 5 at regular intervals (same as ticking noise)
- 4 Ceramic capacitors have 1 Ohm resistance to ground on both poles (Anotated on the pictures)
- After removal of the Battery Charging IC short is still present (Could have been the cause, it's back in there now. Now being the last thing I did before reassembly of the laptop)
- Injection of 1V @ 5Amps max (Probably a bad idea) shows the short to dissapear on 2 of the 3 tested caps (the two in one circle on the front view of the PCB) as in doesn't pull the max allowed amperage of 5 amps but "only" 3 on one side the other being directly ground still triggers the short light on my Lab PSU. 1 Of the 3 caps (the one circled alone in the front view of the PCB) shows no direct connection to ground on both poles at this amperage and pulls -+2.8, 2.5 amps.
- After power injection multimeter still shows the same shorts even though they weren't there anymore when giving the caps 5amps to eat through.
- MOSFETs seem fine around these caps but I don't really know how to test them
From the last time I had such a problem with an Acer Laptop (Aspire 7736zg) it was a bad MOSFET but I didn't need to find it, searching google was enough because of a thread I found here about the issue. Beware I can only test and give further information on weekends as I'm only free then.
Observations :
- The laptop makes a tick sound at regular intervals when plugged in via the charger.
- The laptop negociates with the Power Delivery charger to 20V as expected but shuts back down to 0 then 5 at regular intervals (same as ticking noise)
- 4 Ceramic capacitors have 1 Ohm resistance to ground on both poles (Anotated on the pictures)
- After removal of the Battery Charging IC short is still present (Could have been the cause, it's back in there now. Now being the last thing I did before reassembly of the laptop)
- Injection of 1V @ 5Amps max (Probably a bad idea) shows the short to dissapear on 2 of the 3 tested caps (the two in one circle on the front view of the PCB) as in doesn't pull the max allowed amperage of 5 amps but "only" 3 on one side the other being directly ground still triggers the short light on my Lab PSU. 1 Of the 3 caps (the one circled alone in the front view of the PCB) shows no direct connection to ground on both poles at this amperage and pulls -+2.8, 2.5 amps.
- After power injection multimeter still shows the same shorts even though they weren't there anymore when giving the caps 5amps to eat through.
- MOSFETs seem fine around these caps but I don't really know how to test them
From the last time I had such a problem with an Acer Laptop (Aspire 7736zg) it was a bad MOSFET but I didn't need to find it, searching google was enough because of a thread I found here about the issue. Beware I can only test and give further information on weekends as I'm only free then.
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