198001846 - K073 SEAT BELT UNFASTENED WARNING LIGHT ON

The warning light remains on even when the driver''s seat belt is fastened.If one the passenger''s seat belts is not fastened, the warning light will remain on.
The seat belt not fastened warning light is turned on by a command sent via the B-CAN from the "Air Bag Node" to the Body Computer. The latter sends the signal, via the B-CAN, to the Instrument Panel Node.
Test results
1PRELIMINARY CHECKSAll OKProblems encounteredOperation
Connect an EXAMINER and check the following on CAN NETWORK INFORMATION:- that there are no inactive control units;- that there are no faulty control units;- no control units with faulty CANMove on to Step 21. Fault on CAN network2. Communication with the Body Computer impossible.1. Continue following the instructions given by the diagnostic equipment2. Move on to Step 7
2SWITCH CHECKAll OKProblems encounteredOperation
Check the correct operation of the seat belt unfastened warning light switchMove on to Step 3Switch not operatingReplace the lower branch of the belt    Op. 7065A14 ANCHORAGE ROD FOR , (ONE), FRONT SEAT BELT LEFT OR RIGHT - R.R.
3PASSENGER PRESENCE SENSOR CONNECTIONS CHECKAll OKProblems encounteredOperation
Check that the seat connection is correctly inserted in the connection on the floorMove on to Step 4Passenger presence sensor connector detached from the connection on the vehicle floorFit the seat connector correctly with the vehicle floor connector
4WIRING BREAK CHECKAll OKProblems encounteredOperation
Check for any breaks/tears in the wiring/device using the specific testerMove on to Step 5Presence of cuts/tears in the connecting cables and break in the printed circuitReplacement of the passenger presence sensor    Op. 7065A34 PASSENGER PRESENCE SENSOR ON FRONT SEAT FOR INDICATING SEATBELT UNFASTENED R R
5CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Keep the diagnostic tester connected and check for CAN faults in the AIR BAG NODEMove on to Step 61. Fault on B-CAN network2. Air bag control unit defective1. Move on to Step 112. Replace the Air Bag control unit    Op. 5580C14 AIR BAG ECU - R+R
6CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Using the Examiner in the Instrument Panel Node mode, check that there are no errors and that the parameters are presentMove on to Step 7Presence of errorsContinue following the instructions on the diagnostic instrument
7ELECTRICAL POWER SUPPLY CHECKAll OKProblems encounteredOperation
Check the electricity supply to the Instrument Panel Node is correct.Move on to Step 8Fault in positive electrical supply and/or earthReplace defective component (in the case of a fuse, find out what caused it to blow)
8ELECTRICAL CONNECTIONS CHECKAll OKProblems encounteredOperation
Check the wiring between the Body Computer and the Instrument Panel. In particular, check that each individual pin is properly connectedMove on to Step 9Electrical connections not operationalRenew the damaged electrical connections
9ACTIVE DIAGNOSIS CHECKAll OKProblems encounteredOperation
With the Examiner in Instrument Panel Node mode check that the seat belt unfastened warning light is correctly activated in Active DiagnosisMove on to Step 10The seat belt warning light does not come on correctlyReplace the Instrument Panel    Op. 5560B10 CONTROL PANEL - R+R
10CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Using the Examiner in Body Computer Node mode check that there are no errors and that the seat belt status has changedEnd of diagnosis1. Impossible to connect to the Body Computer control unit2. Presence of errors3. The parameters do not change1. Move on to Step 112. Continue by following the instructions on the diagnostic instrument3. Move on to Step 11
11ELECTRICAL POWER SUPPLY CHECKAll OKProblems encounteredOperation
Check the electricity supply to the Body Computer Node is correctMove on to Step 12Fault in positive electrical supply and/or earthReplace defective component (in the case of a fuse, find out what caused it to blow)
12CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Use an Examiner to check the possibility of connection to the Body Computer NodeEnd of diagnosisImpossible to connect to the Body Computer control unitReplace Body Computer    Op. 5505A35 MAIN BODY COMPUTER/JUNCTION UNIT - R.R.