2427543 - K21 FUEL RESERVE WARNING LIGHT NOT WORKING

With the ignition ON, the fuel reserve warning light does not come on when the tank is at the reserve level
the fuel level message is supplied by the 'body computer node' and is made available to the 'instrument panel node' via the B-CAN.
the 'body computer node' also sends the fuel level sensor error message.
Results of the tests
1CHECKING WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation
Connect the Examiner to the diagnostic socketCheck that there are no faults in the Body ComputerContinue to Step 2Sensor with broken circuit, sensor short circuited, value inconsistent/implausible in relation to actual fuel level.Continue according to the instructions for the diagnostic equipment
2CHECK WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation
Keeping the Examiner connected to the diagnostic socket, check the operation of the fuel reserve warning light in active diagnosisContinue to Step 3The warning light does not come on Replace instrument panel Op. 5560B11
3FUEL LEVEL SENSOR CHECKAll OKProblems metOperation
Check the operation of the fuel level sensor.Continue to Step 4Sensor not workingReplace the fuel pump assembly Op.   1040A70 
4ELECTRICAL CIRCUIT CHECKAll OKProblems metOperation
Check the continuity of the cable between the fuel level sensor, the Body Computer and the instrument panel See   E4010  INSTRUMENT PANEL Continue to Step 5Cables broken/not insulatedRestore the cable continuity/insulation See   E4010  INSTRUMENT PANEL
5CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisThe fault persistsReplace the Body Computer Op. 5505A32