Function: fuel additive function (DW12TED4) Citroen C8 I

Additive

Role

Role of the additive

• To lower the combustion temperature of the particles to 450°C (instead of 550°C)
• To impregnate the particles forming in the combustion chamber
• To propagate combustion of the particles

Description

Additive EOLYS (supplier "RHODIA")

Composition

• Cerine: 4,2% by mass (DP X42)
• Catalytic converter: brown colour
• Solvent product (combustible hydrocarbon)

Additive tank

Description

Data

• Capacity: 5 litres
• Range: 80 000 kms
• Integrated additive injection pump
• Integrated additive minimum level sensor
• 4 orifices

Orifices

• Additive injection pump outlet (10 mm diameter click fit connector)
• Additive injection pump return (8 mm diameter click fit connector)
• Breather (pressure - vacuum safety valve)
• Degassing (overflow)

Refilling: refer to the procedure given in the mechanical file of the vehicle in question

Location

Location: under the fuel tank

Additive injection pump (1283)

Role

The additive injection pump provides the pressure and the flow required in the additive circuit

Description

A - additive return circuit

B - additive low pressure circuit

Make: MARWAL

The additive injection pump consists of the following components

• (1) anti-return valve (additive low pressure circuit)
• (2) low additive level sensor
• (3) filter
• (4) anti-return valve (additive tank return circuit)
• (5) volumetric pump with rollers

The non return valves prevent additive flowing when the additive injection pump return and outlet click fit connectors are opened

Pump delivery: 80 l/h

Normal operating pressure: 3 bars

The additive pump is supplied with 12 volts by the fuel additive ECU in the following cases

• For 5 seconds when the ignition is switched on
• Additive phase

Electrical special features

Control: Fuel additive ECU

Allocation of channels of connector

• Terminal 1: (-) low additive level sensor
• Terminal 2: (+) low additive level sensor
• Terminal 3: 12 volts additive injection pump supply
• Terminal 4: additive injection pump earth
• Terminal 5: not used
• Terminal 6: not used

Location

The pump is submerged in the additive tank

Low additive level sensor (1283)

Role

The sensor informs the additive ECU that the minimum additive level has been reached when there is 0,3 litres in the additive tank

Depending on the information received, the additive ECU informs the engine injection ECU

The injection ECU informs the BSI which requests activation of the following components

• Request to flash the service LED on the control panel (*)
• Request to display a message on the multifunction screen (*)

(*) depending on vehicle equipment

Description

The sensor consists of a thermistor

The information supplied varies depending on whether the thermistor is in the additive or in air (minimum level reached)

Location

The sensor is incorporated into the additive injection pump

Safety valve

Role

Role of the safety valve

• Sealing function (prevents evaporation of solvent, ingress of dust, mud and water)
• Anti-overturn function
• Breather for the additive tank depending on the additive level

Description

(6) vacuum valve (0,036 bar)

(7) overpressure valve (0,05 ± 0,01 bar)

(8) vacuum valve return spring

(9) overpressure valve return spring

Function

• The valve (6) acts as a breather for the additive tank depending on the additive level
• The valve (7) performs a sealing and anti-overturn function

Location

The safety valve is located in the rear left hand wheel arch (behind the mud flap)

Additive injector (1284)

Role

The injector is used to inject a set amount of additive into the fuel tank

Description

A - additive return circuit

B - additive low pressure circuit

Type: WEBER IWP 043

Electrical special features

Control: Fuel additive ECU

Allocation of channels of connector

• Terminal 1: +12 volts supply
• Terminal 2: control

Electrical features: resistance at 25 °C = 14,7 ohms

Location

The additive injector is located on the fuel tank

Fuel tank cap presence sensor (4320)

Role

The fuel filler cap presence sensor informs the additive ECU whether the filler cap is open or closed

Role of the additive ECU depending on the information received: to detect that fuel may be added

Description

(10) permanent magnet

(11) contact

The filler cap is fitted with a magnet and when the cap is closed, the magnet is opposite the contact

Electrical special features

Supply: Fuel additive ECU

Allocation of channels of connector

• Terminal 1: 5 volts supply
• Terminal 2: signal
• Presence of the magnet opposite the contact: resistance = 150 000 ohms
• Absence of the magnet opposite the contact: resistance = 15 ohms

Fuel gauge (1211)

Role

The fuel sender informs the additive ECU of a variation in fuel level through the built-in systems interface

Role of the additive ECU depending on the information received

• Determine the amount of additive to be injected
• To control the additive injection pump
• To control the additive injector

Description

Check: fuel gauge

Built-in systems interface (BSI1)

The BSI sends the following information to the additive ECU

• Engine speed sensor signal (engine running information)
• Vehicle speed information
• Fuel gauge information
• Position of the ignition key

Fuel additive ECU (1282)

Role

The ECU controls additive injection

The ECU software integrates

• Management of the beginning and duration of additive injection into the fuel tank
• Management of the total amount of additive injected since the beginning of the filter's life
• Emergency strategies
• The diagnostic with memorisation of failures
• Dialogue with the injection ECU

Description

The ECU ensures the electrical control of the following elements

• Low additive level sensor
• Additive injection pump
• Additive injector
• Fuel filler cap presence contact
• Catalytic converter downstream exhaust gas temperature sensor

Make: MAGNETTI MARELLI

Electrical special features

Location

Location: on the chassis member near to the base of the right hand B post (according to vehicle)