Fuel gague problems

[Ray]

I have 2003 nissan patrol 3L turbo. When Fridge in caravan is connected fuel gague drops. had wiring checked on van and car. All perfect. When van disconnected no trouble with gague. Any suggestions?

[Yendor]

How is the power and earth for the fridge wired?

Does the power and earth wires come directly from the battery? or is the earth wire connected to the chassis?

I'm guessing the earth wire is connected to the chassis and it's overloading the vehicles original earth circuit.

If it is connected to the chassis I would recommend running it back to the negative of the battery you are using to power the fridge.

Or you can run an earth lead from the negative of the battery and connect it to the chassis just near the battery if you prefer.

[Ray]

Have checked connection. The earth lead is run from the negative of the battery and connected to the chassis just near the battery, so that doesn't work. Any other ideas? The auto electrician has checked it all over to no avail. Thank you very much for your suggestions.

[Yendor]

Is that the original earth you are referring to that connects to the body just under the battery?

The body sits on rubber blocks, you need to run another earth cable to the chassis.