Grounding issue?

[baref00t25]

I have a 2001 Sportster LX. Multi gauge is having odd readings. With only the key on (engine cold) the temperature and oil pressure will increase depending on how many accessories are turned on. The gas gauge and voltage change as well. I've checked every ground I could find (at the batteries, computer, ground block by steering wheel, starter), nothing looks corroded. I have unplugged every connector for every sensor and to the computer and reconnected. I've searched the forum and haven't found anything, but I'm sure someone else has had this issue. What should I check next?

[Bozboat]

I have had the same problem. Key on, engine not running, add the blower and you get more temperature and more gasoline, turn the blower off and both go back down. A real mechanic told me to replace the multi gauge. I have checked every possible ground. The mechanic checked several more I didn't even know existed. I don't know about replacing the multi gauge, as it is only three years old but that is where I am headed.

[FastFreddy]

I would agree with boz. I had similar problems. Voltage gauge read 2-3 volts lower than at battery. I reran new cables to the pos and neg bus bars and it didn't help. I checked voltage right at the gauge and it is fine. Gauge is just reading wrong.

[nuttyskier2002]

You might want to try doing a voltage drop check across the power and the ground circuits. Put you multimeter on DC volts (auto scale). Connect the positive lead to the battery (+) and with the key on........ connect the negative lead to the + post on the multi-gauge. The voltage you read on your multimeter is what is being dropped across all circuits (terminal, connections, ignition switch.........). If it's more than .5 volts start isolating for a bad connection/switch. Do the same test on your ground side as well. You might need to use an extra piece of wire with your meter test leads in order to reach the battery.

[Bozboat]

You might want to try doing a voltage drop check across the power and the ground circuits. Put you multimeter on DC volts (auto scale). Connect the positive lead to the battery (+) and with the key on........ connect the negative lead to the + post on the multi-gauge. The voltage you read on your multimeter is what is being dropped across all circuits (terminal, connections, ignition switch.........). If it's more than .5 volts start isolating for a bad connection/switch. Do the same test on your ground side as well. You might need to use an extra piece of wire with your meter test leads in order to reach the battery.

Thanks I will try that