| STEP | CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK |
|---|
| 1 | Turn the ignition key ON and check that the engine rpm are greater than 60 rpm. | Move on to Step 4 |
| 2 | With the engine idling and warm, with all users off and the accelerator pedal not operated, the engine rpm must be in a range between 780 and 1100 rpm.The test may be considered over. Continue to Step 4 | Move on to Step 4 |
| 3 | With the accelerator pedal operated at full throttle for a short time, engine rpm should roughly coincide with the reading on the instrument panel rev counter.The test can be considered over | Move on to Step 4 |
| 4 | Turn the ignition key OFF.Disconnect the wiring harness connector from engine control unit connector BTurn the ignition key ON.Measure the voltage between control unit pins 43 and 59 (wiring side) See M010 ENGINE MANAGEMENT ECU and Earth, checking it is less than 0.3 V | Repair or if necessary replace the electrical wiring between the engine control unit and the rpm sensor See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT |
| 5 | Turn the ignition key OFF. Measure the resistance between control unit pins 43 and 59 (wiring side) See M010 ENGINE MANAGEMENT ECU and Earth, checking it is greater than 500 kOhmsMove on to Step 7 | Move on to Step 6 |
| 6 | If faults are present, repair or if necessary replace the electrical wiring between the engine control unit and the rpm sensor See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT The test can be considered over | Change the rpm sensor Op. 1060G20 ENGINE RPM SENSOR - R.R. |
| 7 | Disconnect the wiring harness from the rpm sensor. Measure the resistance across control unit pin 43 (wiring side) See M010 ENGINE MANAGEMENT ECU and pin 1 of the solenoid See K046 RPM SENSOR checking that it is less than 5 Ohm. | Repair or if necessary replace the electrical wiring between the engine control unit and the rpm sensor See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT |
| 8 | Measure the resistance across control unit sensor Pin 59 (wiring side) See M010 ENGINE MANAGEMENT ECU and pin 2 of the sensor See K046 RPM SENSOR checking that it is less than 5 Ohm. | Repair or if necessary replace the electrical wiring between the engine control unit and the rpm sensor See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT |
| 9 | Check that the sensor See K046 RPM SENSOR operates correctly: in particular, check for intermittent contacts, missing teeth, incorrect reference point, incorrect gap position, etc. | Restore correct operation, if necessary, replace the faulty components |
| 10 | Change the rpm sensor Op. 1060G20 ENGINE RPM SENSOR - R.R. and check the fault has disappeared | Repair the original rpm sensor and replace the engine management control unit. Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - R.R |