Communication problem between ECU and computer

[Mary]

We're working in a lab on a test bench equipped with a "Honda Civic type R" engine.

It has correctly worked for about 15 hours of tests. Then communication problems appeared, without any test bench change.

The problem is as follow :

When we turn on the engine, the communication between the ECU and the computer is ok. As soon as we load the engine, the communication is lost.

Could you please help us to find out a solution ?

Thank you !

Mary

[Spunkster]

Try it on a real engine in a car and see what happens. If it only happens on yor bench it sounds like a fault in the bench.