am i stupid or what?

i got an oil temp gauge
i m not able to connect it right or i dunno....

if i connect power and ground the gauge shows full temp of 150 ° celsius.
without sensor connected.
even if i connect sensor no change - always full temp.

if i change sensor cable and ground then nothing happens....

i first thought sensor is wrekked and exchanged - no change in behaviour
then i tried another gauge of this set, same ****....

dunno what to do... i connected another gauge for air fuel with same ground and power calble. this one is workin fine....

so i dunno what more to do. perhaps any ideas here?

thanks in advance....

 

what kindof gauge is it? Some types require hooking up switched AND unswitched DC power, plus the signal wire, and a ground...
(at least my Greddy gauges did)

I would read the manual and / or contact the manufacturer.

 

hmm its a plasma

there a 2 power and 2 ground connectors and 1 for the sensor.

1 power and 1 ground for inverter. i connected this to ash tray light. works on both gauges fine.

the other power and ground cables are connected that the gauges can just work when key is in and on pos. 2 or more....

edit
so how do you mean to connect power? 2 times on one gauge?

 

If it's a simple resistor sensor, measure the el. resistant. See if it changes with the temp.
Test the gauge with several resistors (1k, 2k, 10k Ohm etc.)

One wire of the sensor should be connected to the ground, the other to the gauge.