Hello, I would like to read an Adam BCM on the table. I also connected it according to the wiring diagram X1 power supply,X2 Can HS,X3 ignition voltage with a switch. The relays switch at voltage and ignition voltage.But I don't get any communication with the BCM. Whether with MDI2, OPCOM or I/O terminal. The same with a second BCM. I don't understand that many have already done it this way. Maybe someone else has a tip for me. Thank you very much. In addition, I have connected to X2 Can Low, so I have access to the radio at the table.

Your Canbus wires are, probably, the other way around..

X2:23 - CAN LO (OBD pin 14)

X2:24 - CAN HI (OBD pin 6)

X1:1 - Ground (OBD pin 4,5)

X1:2, X1:3, X1:4 - +12V (OBD pin 16)

X3:5 - +12V

BCM and your diag tool must be connected to the same +12/GND points.

Yes, that's how I connected it.

Then you are doing something wrong...

Post your bench setup. What are you trying to read with (what settings for connection?), etc

Good evening, the engine control unit is needed, then the BCM works on the table.

55 minutes ago, Opelfan said:

Buenas noches, se necesita la unidad de control del motor, luego el BCM funciona en la mesa.

Actually, an ECM isn't necessary to communicate with the BCM; simply adding a 120-ohm resistor to the high-speed GM LAN line allows the communication. Also, closing the high-speed GM LAN circuit at X6 plug should enable communication between pins 19-25 (white) and 24-18 (blue).

8 hours ago, Arbe_gtc said:

simply adding a 120-ohm resistor to the high-speed GM LAN line allows the communication

I guess it depends on J2534 adapter too (some have internal resistor/auto-switching)?
Because everything works straight away with mine tool.

Yes, that's exactly what I've found out now. On the X6 pin 19 and 18 two 60 Ohm resistors are looped through. With a 120 Ohm resistor I was able to simulate the ECU. Thanks for the confirmation.

I tried MDI and OPCOM. Which J2534 device are you using?

i use a genuine mdi2, and sometimes VXDiag

35 minutes ago, Opelfan said:

I tried MDI and OPCOM. Which J2534 device are you using?

SM3 with bench cable