iPhone 4S device descriptor request failed

[bogosort]

Hello,

I have an iPhone 4S which I don't have the passcode.

I am trying to reset it using iTunes but it cannot even get detected by my computers.

I tried plugging it in a Windows 11 laptop and a Macbook Air M2.

The current shows 5v 1amp when plugged into a charger,
but it stays at 5v 0.1a when plugged into a PC.

I tried in DFU mode and Recovery mode, I get the same results.

Could it be the cable?

Thank you

[mon2]

Re: iPhone 4S device descriptor request failed

Definitely try another known good cable.

Next, remove all power and check the resistance to ground of the USB vbus power rail on the logic board. That is, a low resistance value could be due to a shorted capacitor.

Next, not sure about this model but the TriStar device is often the next component on the board after the connector. If applicable, a TriStar tester is a quick way to test the state of that component. Perhaps lean on a local mall shop cellphone repair shop to test the TriStar chip.

If the current draw is instantaneous, then often a component is shorting the power rail. The current draw should gradually step up during the boot process.

Do also test the D+ and D- pins in diode mode to confirm that the USB ESD diodes are not blown.

No power. Meter in diode mode.

Red probe to ground, yes red.
Black probe to D+ pin. What is the voltage?

Repeat for D- pin. Post the measurements.