A1502 Trackpad not working

[marce002]

This is really incredible insane, and a total wate of monkey money:

A1502 board is 820 -3536-A no water damage... all works but not the trackpad. keyboard works fine, but fan spins fast. rest is ok macos boots ok... "D" diagnostic shows error NDK003 (aditional ref is PPF003 which denotes keyboard problem, but it works fine... all keys), so:


1) Bought a new trackpad , still not working

ok

2) Bought a new MOTHER!!! (*crazy am i) identical brand new alliexpress, all works but still NO TRACKPAD and fans spin fast.

No keyboard connected , trackpad connected yes ---> same issue
No trackpad connected, keyboard connected yes ---> same issue
No trackpad connected,no keyboard connected ---> same issue
trackpad connected, keyboard connected ---> same issue

so what????? please any any any hibt here?? thanks in advance

[mon2]

Re: A1502 Trackpad not working

See attached.

1) Review the interconnect cable for the trackpad.

2) review the pin pitch (spacing between each such pad) on the trackpad cable.

Be 100% sure if you are replacing this cable that it is the same pitch & same # of contacts.

3) Be sure that the cable is firmly inserted deeply into the FPC blade connector on the mating ends. Clean it with IPA if you suspect any liquid damage - very common - regardless of what anything the client will say.

Take a clear picture and post it here on the flex cable seated inside the connector. I recall a white horizontal line that should be flush with or even inside the FPC connector for a proper mating.

4) Review the voltage on each pin of this trackpad connector. The trackpad is controlled by the Cypress PSOC controller (Cortex M series microcontroller) over the SPI & I2C bus. We want to be sure each is working properly.

[marce002]

Re: A1502 Trackpad not working

thanks Mon

Yes connectors pins/wires are clean and with ohmmeter i have tested all pins with beep (no powered board), and from mother to trackpad connector all wiring is beeping fine.. so flex is ok and connectors too.... volts are as following (*both sides identical)

powering the laptop lid closed:

1 3.3v
2 1.66v
3 3.3v
4 5.12v
5 3.3v
6 0v
7 0v
8 0v
9 0v
10 0v
11 0v
12 0v
13 0v
14 3.3v
15 3.3v
16 3.3v
17 3.3v
18 3.3v

so weird

[mon2]

Re: A1502 Trackpad not working

Try a fresh keyboard and confirm diagnostics does not raise any errors.

Reference:
https://boards.rossmanngroup.com/thr...r-mouse.23580/