Hi, last year I asked BorgWarner directly, please find the answer below.
br Tapsa
Dear Mr,
1. Without diagnostic tool it is difficult to determine the function of the Temp/pressure sensor.
The sensor needs to show a pressure of 0,2MPa or higher for the system to function. Nominal value is 0,4MPa.
2. Listen to the pump motor while the car engine is running at idle speed. The motor should make a small continuous humming sound.
If it is loud, silent, intermittent or changes sound something may be wrong.
When supplied with power externally at ~5volts the current draw should be about 1-2 ampere.
If much higher something is wrong, if much lower something is also wrong.

Med vänliga hälsningar / Best Regards,
BorgWarner TorqTransfer Systems AB