More actions
| IPhone 16 Pro / Pro Max – No Touch Fix | |
|---|---|
| Device | iPhone 16 Pro, iPhone 16 Pro Max |
| Affects part(s) | Main Logicboard |
| Needs equipment | Microscope, soldering equipment |
| Difficulty | ◉◉◉◌ Hard |
| Type | Soldering |
Problem Description
iPhone 16 Pro or Pro Max boots normally and display turns on, but touch is completely unresponsive. This issue stems from a shorted or disconnected signal on the IO_AP_TOUCH_BSYNC1 line, which is responsible for touchscreen communication.
Symptoms
- Screen lights up, no touch response.
- Replacing the display does not fix the issue.
Diagnostic Steps
- Locate IO_AP_TOUCH_BSYNC1 line on display connector (J11800) and measure its diode value.
- If line shows OL, it’s disconnected.
- If line shows 0.000V or close to GND, it’s shorted internally to CPU.
Repair Steps
Case 1: Line is Disconnected (OL)
IO_AP_TOUCH_BSYNC1 line is broken/open between CPU and filter.
- Locate the capacitor (C11727) connected to IO_AP_TOUCH_BSYNC1 line.
- Find IO_AOP_TO_ALS_BSYNC2_CONN on the front prox connector (C11147) (see fig. 2)
- Run a jumper wire from that point on the front prox connector to the output side of the removed filter pad.
- Clean up, reassemble, and test — Touch should now be restored.
Case 2: Line is Shorted Internally in CPU
IO_AP_TOUCH_BSYNC1 shows 0V or is shorted to ground.
- Disconnect the IO_AP_TOUCH_BSYNC1 pad on the display connector to isolate the short.
- Confirm that the line is no longer shorted beyond the capacitor.
- Run a jumper wire from IO_AOP_TO_ALS_BSYNC2_CONN on the Front Prox Flex connector (J11100) to the display connector (J11800). (see fig. 1)
- Clean up and test — Touch should be restored.
