NXT EVO(Left) + SEM + THQ + FSM not detected!

[seign]

Precaution: This is a matter of Left-Handed NXT EVO.

Hi, just received the products and found a big issue.

I have manged to connect 3 pin edge into NXT's 4-pin EXT2 port (at the right side of the circuits, because it is left-hand grip model) and it worked.
However, only one side module is working. When I connect more modules (so total 2 or more side modules), PC does not even recognize whole devices and NXT itself does not turn on.
For example: (by connection order, left to right)

1) NXT(L)+THQ : OK
2) NXT(L)+SEM : OK
3) NXT(L)+THQ+SEM : Failure
4) NXT(L)+SEM+FSM : Failure
5) NXT(L)+THQ+SEM+FSM : Failure (FSM is connected via USB-C cable to SEM)

But, it is strange that when I connect side modules at the left side of NXT as if NXT is right handed, I mean when I connect the cable to the left EXT2 port of NXT's circuits, everything is fine as follows:

1) THQ+SEM+NXT(L) : OK
2) FSM+THQ+SEM+NXT(L) : OK (FSM is connected via USB-C cable to SEM)

But, this setup order is just for test and does not make sense in common use for left-handed.

I have spent whole weekend to find this out and, in my opinion, there is a problem with NXT's EXT2 port for right side attachments (vertically built onto the circuit board). The right side EXT2 port can handle only one external module while the left side EXT2 port works normal as intended.

If my NXT is not a defective product, why can't I attach more than 2 side modules at the right side?

I need solution ASAP. Thanks.

[fallout9]

Service ticket, please.

[seign]

Hi, the core point is like this:
1) There are two EXT ports (4-pin jst ph2.0) in the NXT EVO. Left one is for left-side expansion, and the center one is for right-side.
2) The left EXT is working good. No problem. SEM+THQ+FSM attach to the left EXT port very well and work fine.
3) But, the center EXT has problem. It can not hold 2 or more side modules at a time. If I attach SEM only, it works well but if I attach more module like SEM+THQ, whole system is not working. My PC does not even detect them.

I tried so many times and this is 100% regenerable issue.