Fuel Gauge inacurrate
2002 Mastercraft 197:
I am about to search history again but did not find the advice I was looking for last time. Anyway fuel gauge reads wrong. It does read now. It used to say empty. Dealer replaced fuel gauge, now it reads but it is not accurate. I don't mean not perfectly calibrated. It is not reading correct. It originally always read full way too quickly (probably 3/4 tank or sooner) but it did track down to empty correctly. Now it can say 3/4 tank and be empty. I suspect the sending unit. It is a 3 pin sensor. I disconnected the lead coming to the sensor to measure the incoming signal. I did measure 12 volts supply in the plug. I got 7 volts from the middle pin to ground. I am assuming that is correct. If someone can tell me that probably indicates the sending unit, I 'll just buy one. If not any trouble shooting ideas are welcomed. I went to the automotive store to buy a connector where I could put the sensor in a glass of fuel and test output but they did not have a matching plug.
One other note, I had a polarity issue (hooked battery up backwards while changing in the dark, I bought a battery and the caps were on the wrong terminals.) This was the cause of the fuel gauge being replaced along with a couple of others at the same time. Possibly there is something else that could have fried when that was done. But everything else electric works now including all other gauges, the speed control, blowers, pumps, dashlights, etc.