FUEL GAGE INOP BUT DUMMY LIGHT STILL WORKS

Yes the fuel tank has to come out to change the fuel pump. But are you sure that is the problem ? Your vehicle has a Fuel Pump Flow Control Module (electronic's ) Or is it just your fuel level sensor you want to replace ? And to your question of if the fuel level sensor is bad will the car shut down if the gage says it is emty but it is not? No ,this will not shut down the vehicle. You probably have no idea of the complexity of the electronic's involved an the thing's that can cause the gauge not to work .
Fuel Gage
The instrument panel cluster (IPC) displays the fuel level as determined by the ECM. The IPC receives a serial data message from the ECM indicating the fuel level percent. The fuel gage defaults to empty if:
• The ECM detects a malfunction in the fuel level sensor circuit.
• The IPC detects a loss of serial data communications with the BCM
• The BCM detects a loss of serial data communications with the ECM
When the fuel level is less than a pre-determined value, the low fuel indicator illuminates in the IPC.
Unless you have a factory or professional type scan tool your better off taking your vehicle to a qualified repair shop.

Fuel Gage Inaccurate or Inoperative
Circuit/System Description
The fuel level sender changes resistance based on the fuel level. The engine control module (ECM) monitors the signal circuit of the fuel level sender to determine fuel level. When the fuel tank is full, the sender resistance is low and the ECM senses a low signal voltage. When the fuel tank is empty, the sender resistance is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the fuel level sender in order to calculate the remaining fuel level percent in the tank. The ECM sends the fuel level message via the serial data circuit to the body control module (BCM). The BCM sends the fuel level percent to the instrument panel cluster (IPC) via the serial data circuit for display on the fuel gage.

Circuit
Short to Ground
High Resistance
Open
Short to Voltage
Signal Performance
Fuel Level Sensor Signal
P0462
1
P0463, P0464
P0463
P0461
Fuel Level Sensor Low Reference
--
1
P0463, P0464
P0463
P0461
1. Fuel Gage Inaccurate or Inoperative

Do you know what a DTC is ? diagnostic trouble code !

check power to the sender unit in the fuel tank may be a break in the wire in your trunk/boot. if not change the sender unit.

It could be a loose connection on the gauge or the fuel sending unit.
The fuel sending unit can get worn and have breaks in the contact area that is used to determine float position to send the fuel level reading to the gauge.
I suspect that you have problem with the fuel sending unit considering that the light is on. I am assuming that the light that is on is the "low fuel light". Check your connections at the sending unit if the connections are secure then I would suggest replacing the fuel sending unit.

Fuel level sending unit. I hope it's not, but ya..... it's inside the fuel tank. Also called the float level.

Not an easy task unless you are ready to drop the fuel tank at home.

Some had a small access hole under the back seat so you could get to it easier, but it's not that easy to get the back seat out, and harder to get it back in.

Hope this helps.

The fuel gage shares the same fuse as all the gages, so if the fuel gage is inop and all other gages are working then you have another problem. The most common cause is that the sending unit for the fuel gage inside the fuel tank is defective, that is true 99% of the time in my 35 years of repair work.

Have you checked the fuses? Look in the owner's manual for the locations... you might have just blown one.

If the starter doesn't turn over the battery is dead or you need to replace the starter.

The gas gage not working is caused by the fuel level sender located in the fuel tank this will also need to be replaced.

sounds like you have a bad fuel gauge sending unit common problem it is located inside the the fuel tank with the fuel pump Auto Zone should be able to pull codes to verify this it should say you have a bad fuel level sensor code

check your fuel pump wireing

it is probably the bulb that lights up if it was a fuse you would have something else not working you will have to remove the cluster and replace the bulb in the back