How to read fuel level in case your fuel gauge fails

A broken fuel gauge is a motorist’s nightmare.

You are driving along Thika Road or Mombasa Road, and the needle sits lifelessly on ‘E’ or remains stuck at ‘Full’ for three days straight.

Uncertainty creeps in, as trying to operate the vehicle on an empty tank can ruin the fuel pump, a costly replacement for most modern vehicles.

You do not need to guess.

When the dashboard fails, use these techniques to track your consumption and avoid a dry tank.

The most reliable manual method involves tracking mileage against known fuel consumption.

This requires establishing the vehicle's fuel economy figures.

To calculate this, fill the tank to capacity and reset the ‘Trip A’ counter on the odometer.

The ‘Trip A’ counter odometer is a small, resettable display that tracks the distance of an individual trip, distinct from the main odometer that records the vehicle's total mileage.

To reset it, you typically navigate to the Trip A screen and hold down a button or switch for a few seconds.

Drive until the tank requires refuelling, then fill the tank to capacity again.

Divide the kilometres covered by the litres required to refill the tank.

If a vehicle covers 400 kilometres and requires 40 litres to refill, the consumption rate is 10 kilometres per litre (km/l).

With a known consumption rate, the odometer becomes a precise fuel gauge.

If a vehicle has a 50-litre tank and averages 10 km/l, the total range is 500 kilometres.

Drivers should monitor the trip meter and refuel before approaching the calculated limit.

In many modern vehicles, a gauge failure occurs in the dashboard cluster (the stepper motor) rather than the fuel sender unit inside the tank.

The car's computer (ECU) often retains access to accurate fuel data even if the needle does not move.

An OBD-II scanner, commonly available at auto parts shops from Sh1,500, can access this data.

Plug the device into the diagnostic port usually located beneath the steering column.

Access the ‘Live Data’ stream and locate the ‘Fuel Level Input.’

The scanner will display the fuel level as a specific percentage, bypassing the faulty dashboard display.

Some modern cars feature a ‘Range’ or ‘Distance to Empty’ digital readout separate from the analogue fuel needle.

Often, the stepper motor controlling the physical needle burns out, leading to fuel gauge failure, but the digital sensor remains active..

Cycle through your dashboard menu using the steering wheel controls.

If the ‘Range’ display still shows ‘120km to empty,’ trust the digital number over the broken needle.

This method is strictly limited to motorcycles (boda bodas), older vehicle models, and heavy commercial trucks lacking anti-siphon screens.

Modern passenger vehicles  feature anti-siphon meshes and curved filler necks that prevent solid objects from reaching the tank.

Attempting to insert a rod into a modern saloon or SUV can damage the filler neck components.

For compatible vehicles (such as boda bodas or older lorries), insert a clean rod vertically into the tank while the vehicle is on level ground.

Withdraw the rod to check the fluid line, similar to inspecting engine oil with a dipstick.

This method only confirms whether there is fuel in the tank, but it does not confirm how much fuel there may be in the tank.

With the vehicle stationary and the engine off, physically rock the chassis from side to side.

Listen near the fuel tank location, typically under the rear passenger seats in saloon cars.

A sloshing sound will confirm the presence of fuel in the tank.

Silence indicates the tank is either entirely full (preventing movement) or critically empty.