Bulletins & Advisories Jazz\Fit Fuel Gauge and i-MID Explanation

Discussion in '3rd Generation (2007-2015)' started by Service News, Sunday 8th Aug, 2010.

  1. Service News Staff Managed Dealer Information

    This affects all these chassis code for all Model Years
    Jazz GE6, GE8, GG1, GG2, GG3, GG4, GG5, GG6


    In response to customer comments of inaccurate fuel level display in particular with Jazz models this bulletin aims to provide more details of the operating principle of the fuel level gauge and also the i-MID remaining distance display. Customer comments may include that the low fuel indicator came on too early, when refuelling it was not possible to add more than 30 litres when refuelling or it was possible to drive the vehicle some distance even after low fuel indicator came on with zero km remaining range indicated.

    The reported symptoms can occur on a healthy vehicle due to the vehicle and fuel tank design when considering the following items;
    - The effect of fuel movement in the tank during driving
    - Tolerance of the components measuring the fuel quantity
    - Prevention of fuel flow-back during refuelling
    - Design specification requiring the vehicle to be driven for a minimum length of time, under varied driving conditions, after the low fuel indicator illuminates.

    Symptom 1
    The Customer was unable to add more than approx 30 litres after the low fuel indicator came on.

    Specifications for the low fuel indicator
    - Approx 10 litres of fuel could remain in the fuel tank when the low fuel indicator comes on.
    - When refueling at a fuel station, the auto stop function on the pump nozzle works when the fuel amount in the tank reaches approx 40 litres. If refueling is stopped when the auto stop first engages, the total fuel amount could be 2 litres less than its total tank capacity of 42 litres.

    As described above, it is possible for the tank to be full after only approx 30 litres of fuel has been added when the low fuel indicator has come on.

    Symptom 2
    Complaint 2: Customer was able to drive some distance after the MID range display shows zero miles remaining.

    i-MID (multi information display) displays 0 miles as the range (estimated distance) when the fuel gauge indicates E (Empty). However, approx 7.5L fuel could still remain in the fuel tank. Depending upon the conditions further driving is possible on the remaining quantity of fuel but cannot be guaranteed and is not advisable.

    i-MID Remaining Range Calculation
    Fuel remaining amount is calculated by deducting the amount of fuel injected from the initial fuel amount in the tank right after refueling.

    Refuelling judgement method
    Refuelling is judged to have been carried out when the tank becomes full or the amount of fuel in the tank has increased by at least 5 Litres.
    When refuelling is judged to have been carried out the remaining range is initially estimated using the calculation table line (A). During driving the most appropriate calculation table is chosen depending upon the fuel economy after driving a certain distance (examples B) and the range is then recalculated. This process will continue as the fuel quantity decreases and the remaining range will be seen to fluctuate up and down depending upon the driving conditions.
    Jazz Fuel levels.
    Once the low fuel indicator comes on (C), the calculation table in use at that time is maintained, even though the actual fuel consumption may change and
    the remaining distance will reduce to zero at the point the gauge reaches the "Empty" position. Once the remaining distance has reached zero a
    reserve quantity remains in the tank and further driving may be possible but this is not advisable.

    Diagnostic Procedure
    Should reported symptoms differ from those described above carry out the following checks to confirm correct operation;
    Gauge Module Check
    Fuel Sender Unit Test