01 Should I Press the Clutch Every Time I Need to Apply Brakes… • 02 Does Auto Start - Stop Wear Out a Starter? • 03 How to Schedule Your Automotive Maintenance • 04 Why You Need to Press the Brake Pedal When Shifting from P … • 05 If You Can't Afford Repairs, You Can't Afford the Car • 06 The Most Common Car Repair Mistake and How to Avoid It • 07 The Right Way to Charge EV Batteries: Lessons from Stanford… • 08 The Complete Guide to the Major Parts of an Excavator • 09 Engineers Reveal Why Most Car Doors Are Designed To Rip Apa… • 10 The Technology That Allows Mechanics to Diagnose Cars Witho… •

DTC codes / Jaguar codes / P1199

P1199 · JaguarFuel Level Input Circuit Low

P1199 on a Jaguar means the fuel level input circuit is reporting a low voltage condition to the instrument cluster or engine control module. The computer expects a variable voltage from the fuel tank sender that rises and falls with the fuel level, and it has detected a signal that stays below the normal operating range for too long.

SystemPowertrain
Code typeJaguar specific
SeverityLow
Fix difficultyIntermediate
AreaFuel and air metering

Symptoms you may notice

  • Fuel gauge reads empty or fluctuates erratically even when the tank is full
  • Low fuel warning light stays on constantly regardless of actual fuel level
  • Often no symptoms besides the warning light, with the gauge appearing to work normally at times
  • Fuel gauge drops to empty shortly after refuelling and then recovers
  • Distance-to-empty or fuel economy displays become inaccurate or show dashes
  • In some cases the engine may run poorly if the module uses fuel level for purge or evap strategy

Common causes, most likely first

  1. Faulty fuel level sender unit in the tank, worn or dirty resistance track causing a low signal
  2. Damaged or corroded wiring between the fuel tank sender and the instrument cluster or body control module
  3. Poor electrical connector at the fuel tank or behind the instrument cluster, often due to water ingress
  4. Failed fuel pump module assembly where the sender is integrated and the internal contact fails
  5. Instrument cluster or body control module internal fault misreading the sender signal
  6. Grounded signal wire shorting to chassis, pulling the fuel level input voltage low
  7. Aftermarket alarm or remote start installation tapping into the fuel gauge circuit incorrectly

How to diagnose and fix it

  1. Connect a scan tool and read live fuel level sensor voltage and fuel gauge data to confirm the low signal
  2. Visually inspect the fuel tank sender connector and wiring for corrosion, chafing, or water damage
  3. Disconnect the sender and measure resistance across the sender terminals while moving the float arm through its range
  4. Check the signal wire from the sender to the cluster for a short to ground using a multimeter and wiring diagram
  5. If resistance is out of specification or erratic, replace the fuel level sender or fuel pump module assembly
  6. If wiring and sender test good, substitute a known-good instrument cluster or body control module to rule out internal faults
  7. Clear the code and verify the fuel gauge reads correctly through a full sweep and test drive

Before you replace the fuel pump module

  • A common mistake is replacing the entire fuel pump module when only the sender card is faulty, but on many Jaguars the sender is available separately and costs far less.
  • Water ingress into the connector at the top of the fuel tank is a frequent cause on older Jaguar saloons, and the pins can look clean until you pull the connector apart.
  • The fuel level signal often passes through the body control module before reaching the gauge, so a fault in the module or its grounds can set P1199 even when the sender is perfect.
  • Aftermarket fuel additives or contaminated fuel can leave a varnish film on the sender resistance track, causing a low signal that clears temporarily after a tank of fresh fuel.
  • A weak battery or poor ground can cause the module to misread the fuel level input, so always check charging system health before condemning the sender.

Can I keep driving with P1199?

The car remains safe to drive because this fault only affects fuel gauge accuracy, but you should refuel based on mileage rather than the gauge until it is fixed. Avoid running the tank very low, as you may run out of fuel unexpectedly if the gauge reads lower than actual.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for Jaguar vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage