E6X Coms stopped working, Which chip is Coms chip?

[bmgjet]

Hello,
I have a E6X that has been working and just today stopped talking over serial connection.
Car still runs and from my reading on the forum everything leads to a com chip gone bad.

I have opened up the ECU and there is no visable damage but I cant indentify which chip is the coms one responsiable for the serial port since there are 4 MAX chips with the same part number that handle serial com stuff.

2 up by the loom plug and 2 either side of the internal map sensor.
Which one handles the Serial port data?

I tried to trace them back following the traces from TX and RX pin but they disapare under some resistors and I dont want to remove anything I dont have to.

[HaltechMatthew]

Send it back, it can still be repaired at the moment.

[bmgjet]

I just need to know which one of the 4 serial chips is the one that handles the Serial Com so I dont have to replace all of them.
I do plenty of ECU repairs and tuning so its pointless to strand this car for a few weeks and paying some one else to do a fix that would take me 10mins and $1.50 part.

Im guessing its the bottom chip under the MAP sensors since iv traced the TX pin and trace though a few resistors back to that.

[bmgjet]

Just replace all 4 and its working now.