| STEP | CHECK TO BE PERFORMED | REMEDIAL ACTION IF THE CHECK IS NOT OK |
|---|
| 1 | Preheating control unit power supply checkTurn the key to the MAR positionUsing an Examiner in Voltmeter mode, check that there is a 12 V battery voltage between pin 3 and earthMove on to Step 2 | Restore the electrical continuity of the supply lead See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Restore the 15 A fuse (F11) in the fuse box after having identified the cause of the problem.Replace main relayReplace the junction unitOp. 5505A13 |
| 2 | Check earth connectionDisconnect negative battery cableDisconnect the wiring from the glowheater plugs control unitReconnect the negative battery cableUsing an Examiner In Ohmmeter mode, connect between pin 1 of the wiring and earthCheck that the resistance is less than 1 OhmMove on to Step 3 | Restore the electrical continuity of the earth lead See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT |
| 3 | Check on preheating control unit activation control by engine control unit Turn the key to the ON positionWith the Examiner in voltmeter modecheck that there is a voltage of 0 V between pin 2 and earthCheck that the voltage switches to about 9 Volt after a few secondsStart the engine and check that the voltage switches firstly to 0 Volt and then to around 9 VoltMove on to Step 4 | Restore the wiring between the engine management control unit and the heater plugs control unit See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT If the voltage is interruptedReplace the engine management control unit Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - R.R and carry out the correct operation renewal procedure |
| 4 | Check on return signal from preheating control unit to engine management control unitWith the Examiner in voltmeter modeTurn the ignition to the ON position and check that there is a voltage of around 10 V between pin 5 and earth See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Start the engine and check that the voltage switches to about 0 VoltMove on to Step 5 | Restore the wiring between the preheating control unit and the engine control unit.If OKReplace heater plug preheating control unit Op. 5520C20 HEATER PLUGS CONTROL UNIT - R.R and carry out the correct operation renewal procedure |
| 5 | Check on power supplyCheck that there is a 12 Volt voltage present at pin 30 See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Move on to Step 6 | Restore the wiring between the preheating control unit and the fuse box on the batteryRestore the power fuse after having identified the cause of the problem. |
| 6 | Heater plugs power supply checkStart the engine and check that the battery voltage arrives correctly to the individual glow plugs during the preheating stage See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT The test can be considered over. | Restore the wiring between the preheating control unit and the glow heater plugsReplace the preheating control unit Op. 5520C20 HEATER PLUGS CONTROL UNIT - R.R and carry out the correct operation renewal procedure. |
