Jaguar fuel gauge problems

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The sending unit is in the gas tank...(its #9) ..good luck

You need to replace the fuel level sending unit, it is located inside the fuel tank.

Hi, the problem is in the sending unit located at your gas tank. I believe it is on the top of your tank, and you will need to remove either the rear seat to get to it, or what ever is directly over the tank. It may have a bad wire connection at the float assembly and sending unit that tells your gauge the amount of fuel is in the tank. If you are not sure, pick up a manual at any auto parts store, Chiltons, Haynes which will guide you through it.Your gauge is OK, it will be the sending unit that tells the gauge. I wish you the best on this,
Shastalaker7

I'm not sure I am understanding your question. The low Fuel indicator light comes on, depending on how sensitive it is set, when you have between 2 and 5 gallons of gas left in the tank. This also depends on how accurate your fuel level sending unit is reading the fuel level in the tank. The low fuel level light depends on the level of fuel in the tank itself but other than using that sensor it has nothing to do with the fuel gauge itself. The fuel gauge may or may not be accurately showing the fuel level.

FUEL SENDING UNIT IN THE FUEL TANK FAULTY.THE FLOAT ARM ATTACH TO SENDING UNIT.THE FUEL SENDING IS A RHEOSTAT WITH ELECTRICAL CURRENT FLOWING TO IT.YOU HAVE A COIL OF RESISTANCE WIRE IN RHEOSTAT.WHEN FLOAT+ ARM RISE WHEN PUMPING MORE FUEL IN TANK THIS CAUSE MORE CURRENT FLOW THROUGH COIL FROM RHEOSTAT TO FUEL GAUGE WHICH CAUSE FUEL GAUGE MOVE TO FULL MARK.WHEN FUEL LEVEL DROP THE FLOAT + ARM DROP CAUSE LOW CURRENT THROUGH RHEOSTAT COIL WIRE IN WHICH CAUSE FUEL GAUGE NEEDLE TO DROP SHOWING LOW FUEL LEVEL IN THE FUEL TANK.

Well that tells me that someone installed the wrong fuel level sensor. Your going to have to drop the tank and pull the pump and float assymbly out. Then go to a parts store and get a sending unit that has the opposite resistance of that sending unit. Just wait until the tank is empty so its a lot lighter. You can call the parts store or go down and see if there is multiple sending units. The sending units work by resistance, when the tank is full the float moves up and turns a wheel in the sending unit, which either removes or increases the resistance causing the gauge to lower. The sending units either give full resistance at full or no resistance at full and then changes as the level goes down until it does the opposite at empty.

Change the fuel gage sender unit in tank.its faulty.

this problem is caused by the sending unit inside the fuel tank, very common problem.

Normally this problem is due to a bad sending unit. The sending unit is the actual device which transmits the level of fuel in the tank to your fuel gauge. The most common cause is a stuck float. The device works by means of a flotation device, often made of a petroleum resistant plastic encasing a foam or cork "float, " which is attached to a light weight metal arm. The arm moves as the float raises and lowers with the level of fuel. This arm connects to a switch which increases and decreases resistance in the circuit. If the arm is stuck or if the float is allowing fuel in it you will get an inaccurate reading. A "logged" float (one filled with fuel) usually reads below the level, whereas an arm which is sticking will read above the level. Now, if the gauge has been reading this way since the car was brand new, the other likely cause is that the needle may have been improperly placed on the gauge at the factory, or the windings in the gauge may be under or over wound causing the inaccurate reading. If you are mechanically inclined you may be able to replace the sending unit yourself. Keep in mind this can be a dangerous procedure for a first time mechanic as it may involve removing the fuel tank from the vehicle. Some vehicles offer access to the upper portion of the fuel tank via an opening located in the trunk under the trunk mat/carpet or under the back seat. If this is the case removal of the fuel tank is not normally necessary, but you will still be working with the fuel tank. If you are able to do this procedure in the vehicle, keep in mind you will first want to disconnect power to the fuel pump and sending unit. You can disconnect the negative battery cable, but I believe on an the kadette you will need to obtain a special cable from your local auto part supply to maintain power to the ECU or PCM to prevent damage to the computer or loss of programming. At the very least remove the fuel pump relay and disconnect any fuse/relay related to the dash gauges prior to beginning this operation. Also be sure to remove the fuse for any possible ignition source inside your vehicle, such as dome and courtesy lights. Keep cell phones away from the work area as well. If you use a "trouble light" be sure it is marked as safe for use near fuel fumes. Keep doors or windows of the vehicle open to allow vapors to escape so you don't suffer any ill effects and to further reduce ignition hazards. If you must remove the fuel tank, practice good safety. Do not be under the tank at any time. Be sure to remove it with very little fuel in it. Go slowly and be sure you don't break any wires or lines. It is a very involved process and may be best left to a certified mechanic or at least one who is very experienced. Keep me posted and let me know if this helps!

You don;t say whether the fuel gauge is reading accurately, or whether it's always on empty. If the gauge is always showing empty, it's most likely a problem with the sending unit in the fuel tank. Check the resistance across the two terminals of the sending unit.

On a C900, the fuel sender level unit is separate from the fuel pump and located on the right side top of the tank, accessible by removing the trunk floor lift up panel (the pump is located on the left side top of the tank.
Possible problems are: electrical line off or broken, float not working (it's fairly delicate); or gauge not working.

Test the resistance of the sending unit with the lines disconnected, the resistance should be 2.6 to 3.8 ohms full tank, 63.3 to 67.5 ohms empty tank; and test for voltage across the top of the sender unit, if no voltage, that's likely the problem!

If the gauge is otherwise reading accurately (showing 'full' for a full tank, etc) then the problem is likely a gauge malfunction and can be simply replaced.

Good luck!

Saabreur