ECU Master PMU16 to USB to CAN error

I am a but stumped on the ECU master PMU16 CAN protocol when using the ECU Master USB to CAN module. I am getting a CAN communication error. Checked connections to the CAN 1 H and CAN1 L to the PMU16 and using one additional terminated resistor per instructions. Wired CAN 1 setup per the instructions on ECU master instructional.

I sent the PMU/ DB9 cable and USB to can unit back to ECU master to inspect as RMA and they said it was all fine. Upon receiving the unit back, I replaced the DB9 connector and setup all new wiring and still seeing the same scenario. The solid red LED indicator on USB to CAN module as well as "cannot connect" when attempting to detect through ECU master Lite. Checked ohm readings and its showing 120ohms. Any suggestions on wiring or something I've overlooked? BTW i bench tested multiple wiring configurations through CAN 1 using desktop computer and also a laptop. The USB to CAN is showing connection to the laptop but no CAN communication to the PMU.

Do you have any other CAN devices on the Bus that could have internal resistors? When you say you check the ohm reading, was it connected in the circuit? If so, you should have 60 ohms reading, as 2x 120ohms resistors in parallel = 60 ohms.

Also did you check that the communication speed is set up correctly?

Can 1 is dedicated to USB to CAN and PMU16 only. CAN 2 is not connected to anything at the moment. The ECU master CAN to USB has a built in resistor switch on/off which is being used as the second end for termination. My mistake on my previous post it was reading 60 ohms when probing at the main connector for the PMU16 unit. 120 ohm when the termination switch is off.

In regards to com speeds. The ECU lite program has the ability to setup automatically but CAN 2 BUS speeds can be changed once communications is achieved. From what I have researched there is no mention of different speeds for CAN1 communication since this is a dedicated BUS.

It's a bit hard to do remote diagnosis, but at this time I would probably remove and reinstall the drivers, and I would check the power and ground of the PMU.

The issue was a faulty connector pin at the main harness plug. Thanks for the assistance Frank!

Yeah, glad you found your issue and that I could help :)