Flow chart
67: channel E2 of the 32 way grey connector (CME) relay control of the pre-postheating control unit
88: channel A4 of the 32 way grey connector (CME) diagnosis of the pre-postheating control unit
| BSI1 | built-in systems interface |
|---|---|
| 0004 | instrument panel |
| 1158 | pre-post heating control unit |
| 1160 | pre-heater plugs |
| 1320 | engine ECU |
| no. of link | signal | nature of signal |
|---|---|---|
| 1 | request for lighting of pre-heater warning lamp | CAN |
| 2 | lighting of pre-heater warning lamp | Comfort VAN |
Pre-heater plugs (1160)
Role
The pre-post heating glow plugs allow a rapid temperature rise in the combustion chambers during the starting phase
Description
11 volt pre-heater plugs
Total length of 118,5 mm
Composition of the pre-heat glow plugs
- A heating resistor
- A metallic protective cover
Pre-post heating control unit (1158)
Role
The housing supplies the pre-heating plugs with electricity following the injection ECU's commands
Description
The pre-post heating times are determined by the injection ECU
In the event of a malfunction of the pre-postheating control unit, the injection ECU memorises a fault
Electrical special features
Allocation of channels of connector
- Line N° 1: supply of pre-heater plug, cylinder N°3
- Line N° 2: supply of pre-heater plug, cylinder N°1
- Line N° 3: diagnosis of the pre-postheating control unit
- Line N° 4: permanent +12 volts
- Line N° 5: earth
- Line N° 6: supply of pre-heater plug, cylinder N°4
- Line N° 7: supply of pre-heater plug, cylinder N°2
- Line N° 8: relay control of the pre-postheating control unit
Location
| reference | designation |
|---|---|
| 3 | pre-heater plug |
| 4 | electrical harness |
| 5 | pre-post heating control unit |
| 6 | engine cylinder head |
Pre-postheating
The times for pre-heating and post-heating are determined by the engine ECU as a function of the temperature of the engine coolant fluid at idling speed and at altitude
Pre-heating operation
| engine coolant temperature | pre-heating time | idling speed | Préchauffage: altitude exceeding 1000 m | Préchauffage: altitude exceeding 1500 m | Préchauffage: altitude exceeding 2000 m |
|---|---|---|---|---|---|
| 80 °C | 0 seconds | 750 rpm | 0 seconds | 0 seconds | 0 seconds |
| 20 °C | 0 seconds | 800 rpm | 0,5 seconds | 2 seconds | 3 seconds |
| 0 °C | 0,5 seconds | 890 rpm | 1 seconds | 5 seconds | 5 seconds |
| - 10 °C | 5 seconds | 950 rpm | 5,5 seconds | 9,5 seconds | 9,5 seconds |
| - 20 °C | 5 seconds | 1050 rpm | 5,5 seconds | 9,5 seconds | 9,5 seconds |
| - 25 °C | 10 seconds | 1075 rpm | 10,5 seconds | 12,5 seconds | 12,5 seconds |
| - 30 °C | 15 seconds | 1100 rpm | 15 seconds | 15 seconds | 15 seconds |
Postheating operation
The postheating extends the operating of the pre-heater plugs after the starting phase
The post-heating enables the emission of pollutants in the first few minutes after starting to be reduced
The post-heating reduces the emissions of blue smoke including at altitude
| engine coolant temperature | pre-heating time | idling speed | post heating |
|---|---|---|---|
| 80 °C | 0 seconds | 750 rpm | 0 seconds |
| 20 °C | 0 seconds | 800 rpm | 0,5 seconds |
| 0 °C | 0,5 seconds | 890 rpm | 180 seconds |
| - 10 °C | 5 seconds | 950 rpm | 180 seconds |
| - 20 °C | 5 seconds | 1050 rpm | 180 seconds |
| - 25 °C | 10 seconds | 1075 rpm | 180 seconds |
| - 30 °C | 15 seconds | 1100 rpm | 180 seconds |
Parameters which could interrupt post-heating
- Coolant temperature above 65°C
- Injected fuel flow exceeding 30 mm3 (between 1200 and 1500 rpm)
- Injected fuel flow exceeding 10 mm3 (2500 rpm)
- Injected fuel flow exceeding 5 mm3 (330 rpm)
- Engine speed above 3500 rpm
- Battery voltage less than 7,5 volts