Instrument temp / fuel changes with elec load

I have an issue that the temperature goes up by 12 deg when I put the interior fan from speed 0 to speed 3. Also the fuel gauge can vary by 4 litres. I have checked all the earths and connectors and cleaned them.

I am worried that the voltage regulator is failing on the Stack unit.

Has any one else had this problem?

I think it’s quite common and is almost certainly due to voltage drops as the load increases, although 12 degrees does seem a lot. Could it be a bad earth somewhere…

I agree with Mike - my temp reading used to jump by 8-10 deg when using the interior fan.

Thansk for these. I will run a temporary seperate earth and see where this takes me.

I took the Stack unit out and found a 30Kohm resistance on the earth. In the end I traced it to tone of the earth eyelets on the battery. The clamp is the cheep pressed on and the eyelets were not making contact properly. I have replaced the clamp with a cast one and cleaned/greased the eyelets and now every thing is fine with just a 2 deg rise with a completed electrical load.