Diesel preheating relay check
- Make
- Fiat
- Model
- Croma Factory Service Manual
- Year
- 2005–2010
- Section
- Engine starting › Diesel preheating relay check
DIESEL PREHEATING RELAY CHECK
| CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK | |
|---|---|---|
| 1 | Connect a charged battery in parallel with the vehicle battery. Start the engine. Move on to Step 13 | Move on to Step 2 |
| 2 | Turn the ignition key OFF. Disconnect the cable loom connector from engine management control unit connector A See M010 ENGINE MANAGEMENT CONTROL UNIT Do not engage any gear. Turn the ignition key ON. Connect the emergency starting lead for a maximum of 3 secs. between pin 72 of control unit wiring side connector A and earth, checking that the engine does not start. | Replace the engine management control unit |
| 3 | Turn the ignition key OFF. In the engine compartment junction unit, remove relay T9 from the case (it is the one the middle of the bottom row) See B001 ENGINE COMPARTMENT JUNCTION UNIT Turn the ignition key ON. Measure the voltage between Pin 85 of the base unit and Earth, ensuring it is less than 0.3 V. Move on to Step 5 | Move on to Step 4 |
| 4 | If faults are present, repair or, if necessary, replace the electrical wiring between the engine management control unit and the engine compartment junction unit. See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 5 | Turn the ignition key OFF. Measure the resistance between Pin 72 of control unit connector A and Pin 85 of control unit connector A to ensure it is less than 5 Ohm | Move on to Step 4 |
| 6 | Turn the ignition key OFF. Measure the voltage between Pin 30 of the control unit base unit and the earth, ensuring it is greater than 11 V. See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 8 | Move on to Step 7 |
| 7 | If faults are present, repair or, if necessary, replace the electrical wiring between the battery and the engine compartment junction unit. The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 8 | Connect the emergency starting lead for a maximum of 3 secs. between pins 30 and 87 of the control unit base, checking that the engine does not start. See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 12 | Move on to Step 9 |
| 9 | Measure the resistance between Pin 87 of the control unit base and Pin 50 (wiring side) of the starter motor, checking that it is less than 5 Ohm See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 11 | Move on to Step 10 |
| 10 | If faults are present, repair or if necessary replace the electrical wiring between the engine compartment junction unit and the starter motor See E5010 STARTING AND RECHARING The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 11 | If faults are present, repair or if necessary replace the electrical wiring between the battery, starter motor and earth See E5010 STARTING AND RECHARING The test can be considered over | Replace the starter motor Op. 5520b12 STARTER MOTOR - R+R FOR VERSIONS WITH A/C |
| 12 | Turn the ignition key ON. Measure the voltage between Pin 86 of the control unit base unit and the earth, ensuring it is less than 11 V. See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 10 | Replace the starter motor Op. 5520b12 STARTER MOTOR - R+R FOR VERSIONS WITH A/C |
| 13 | Turn the ignition key to the OFF position and extract it. Turn off all the electrical consumers. Charge or, if necessary, replace the battery. Disconnect the connector from the battery cable loom. Measure the current between pin A (wiring side) and pin A (component side) of the battery, checking that it is less than 80 mA. Move on to Step 15 | Move on to Step 14 |
All the vehicle systems should be switched off during the test. Close the doors and the tailgate, disconnect the engine compartment lighting.
| CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK | |
|---|---|---|
| 14 | The stall current for one or more consumers is too high. During the search for faults in the wiring, the sections of the wiring for the allocated connectors can be separated. When the stall current moves to the permitted value, after the section has been separated, this means that the fault is located in this section of the wiring. The test can be considered over | |
| 15 | Reconnect the connector to the battery cable loom. Start the engine and switch on all the electrical consumers. Let the engine speed reach 3000 rpm. Measure the voltage between pin A and pin B of the battery (wiring side), checking that it is less than 12.5 V | Replace the battery |
| 16 | Turn the ignition key OFF. Disconnect the connector from the alternator cable loom. Turn the ignition key ON. Measure the voltage between Pin D+ (wiring side) of the alternator and earth, checking that it is more than 11 V | Move on to Step 18 |
| 17 | If faults are present, repair or if necessary replace the electrical wiring between the battery, alternator and earth See E5010 STARTING AND RECHARING The test can be considered over | Replace the alternator. |
| 18 | If faults are present, repair or if necessary replace the electrical wiring between the alternator and the engine management control unit | Replace the engine management control unit |
| CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK | |
|---|---|---|
| 1 | Connect a charged battery in parallel with the vehicle battery. Place the gear lever in position P. Start the engine. Move on to Step 15 | Move on to Step 2 |
| 2 | Turn the ignition key OFF. Disconnect the cable loom connector from engine management control unit connector A See M010 ENGINE MANAGEMENT CONTROL UNIT Place the gear lever in position N. Turn the ignition key ON. Connect the emergency starting lead for a maximum of 3 secs. between pin 72 of control unit wiring side connector A and earth, checking that the engine does not start. | Replace the engine management control unit |
| 3 | Turn the ignition key OFF. In the engine compartment junction unit, remove relay T9 from the case (it is the one the middle of the bottom row) See B001 ENGINE COMPARTMENT JUNCTION UNIT Turn the ignition key ON. Measure the voltage between Pin 85 of the base unit and Earth, ensuring it is less than 0.3 V. Move on to Step 5 | Move on to Step 4 |
| 4 | If faults are present, repair or, if necessary, replace the electrical wiring between the engine management control unit and the engine compartment junction unit. See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 5 | Turn the ignition key OFF. Measure the resistance between Pin 72 of control unit connector A and Pin 85 of control unit connector A to ensure it is less than 5 Ohm | Move on to Step 4 |
| 6 | Turn the ignition key OFF. Measure the voltage between Pin 30 of the control unit base unit and the earth, ensuring it is greater than 11 V. See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 8 | Move on to Step 7 |
| 7 | If faults are present, repair or, if necessary, replace the electrical wiring between the battery and the engine compartment junction unit. The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 8 | Connect the emergency starting lead for a maximum of 3 secs. between pins 30 and 87 of the control unit base, checking that the engine does not start. See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 12 | Move on to Step 9 |
| 9 | Measure the resistance between Pin 87 of the control unit base and Pin 50 (wiring side) of the starter motor, checking that it is less than 5 Ohm See B001 ENGINE COMPARTMENT JUNCTION UNIT Move on to Step 11 | Move on to Step 10 |
| 10 | If faults are present, repair or if necessary replace the electrical wiring between the engine compartment junction unit and the starter motor See E5010 STARTING AND RECHARING The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 11 | If faults are present, repair or if necessary replace the electrical wiring between the battery, starter motor and earth See E5010 STARTING AND RECHARING The test can be considered over | Replace the starter motor Op. 5520b12 STARTER MOTOR - R+R FOR VERSIONS WITH A/C |
| 12 | Turn the ignition key ON. Measure the voltage between Pin 86 of the control unit base unit and the earth, ensuring it is less than 11 V. | Replace the starter motor Op. 5520b12 STARTER MOTOR - R+R FOR VERSIONS WITH A/C |
| 13 | Measure the resistance between Pin 1 (wiring side) of the control unit and the output contact of fuse F24 (first on the left in the upper row), checking that the resistance is greater than 5 Ohms. | Replace the automatic transmission control unit Op. 2135B52 ELECTRONIC AUTOMATIC TRANSMISSION ELECTRIC CIRCUIT -ECU MOUNT R R |
| 14 | If faults are present, repair or, if necessary, replace the electrical wiring between the engine compartment junction unit and the automatic transmission control unit. See E7050 AUTOMATIC TRANSMISSION The test can be considered over | Replace the engine compartment junction unit Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R. |
| 15 | Turn the ignition key to the OFF position and extract it. Turn off all the electrical consumers. Charge or, if necessary, replace the battery. Disconnect the connector from the battery cable loom. Measure the current between pin A (wiring side) and pin A (component side) of the battery, checking that it is less than 80 mA. Move on to Step 17 | Move on to Step 16 |
All the vehicle systems should be switched off during the test. Close the doors and the tailgate, disconnect the engine compartment lighting.
| CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK | |
|---|---|---|
| 16 | The stall current for one or more consumers is too high. During the search for faults in the wiring, the sections of the wiring for the allocated connectors can be separated. When the stall current moves to the permitted value, after the section has been separated, this means that the fault is located in this section of the wiring. The test can be considered over | |
| 17 | Reconnect the connector to the battery cable loom. Start the engine and switch on all the electrical consumers. Let the engine speed reach 3000 rpm. Measure the voltage between pin A and pin B of the battery (wiring side), checking that it is less than 12.5 V | Replace the battery |
| 18 | Turn the ignition key OFF. Disconnect the connector from the alternator cable loom. Turn the ignition key ON. Measure the voltage between Pin D+ (wiring side) of the alternator and earth, checking that it is more than 11 V | Move on to Step 20 |
| 19 | If faults are present, repair or if necessary replace the electrical wiring between the battery, alternator and earth See E5010 STARTING AND RECHARING The test can be considered over | Replace the alternator. |
| 20 | If faults are present, repair or if necessary replace the electrical wiring between the alternator and the engine management control unit | Replace the engine management control unit |
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