Hello, I have the following problem. I drive a Chevy K30 ex military. Now these vehicles have no display instruments installed. However, since I would like to have some information about pressure and temperatures to spare the engine/gear, I have installed instruments from Rais HP. So far, this has also worked well. If I turn on other consumers (e.g. charging surface lighting) the instruments start to spin(e.g. the oil pressure drops completely and the outside temperature drops off I turn it off again everything is normal. The instruments are connected as indicated in the description. The duration plus has its own fuse in the fuse box. Since the vehicle has a large mass rail, the ground lines are connected to it. Ignition plus is connected to ignition plus. Does anyone have an idea what this can be or what I did wrong? Am really in despair because I can’t find the mistake.