Electronic control system of diesel engine (Mercedes-Benz E-Class W124)

Contents: Electronic control unit ↡ Overload relay ↡ Crankshaft speed sensor ↡ Coolant temperature sensor ↡ Electromagnetic actuator elr ↡ Exhaust Gas Recirculation System…↡ Air flow meter ↡ Engine Air Intake Temperature Sensor ↡

Electronic control unit

Removal

1. The EDS electronic control unit is installed in the rear of the engine compartment behind the bulkhead.

2. Remove the ground cable from the battery.

3. Disconnect the multi-pin electrical connector from the electronic control unit.

4. Remove the screws and remove the electronic control unit from the engine compartment bulkhead.

Installation

1. Installation is carried out in the reverse order of removal.

Overload relay

Removal

1. The relay is mounted on the main unit next to the EDS ECU. The relay contains fuses and diodes, the functions of which include protecting the EDS from overcurrent and voltage surges.

2. Remove the ground cable from the battery.

3. Remove the relay from its socket.

Installation

1. Installation is carried out in the reverse order of removal.

Crankshaft speed sensor

Removal

1. Remove the ground cable from the battery.

2. Disconnect the crankshaft sensor electrical connector, which is located in the engine compartment behind the battery.

3. The crankshaft sensor is mounted on the mating surface between the cylinder block and the clutch housing above the starter. Unscrew the bolt and remove the crankshaft sensor from the clutch housing. Remove the gasket.

Installation

1. Installation is carried out in the reverse order of removal.

Coolant temperature sensor

Removal

1. Drain some of the coolant from the cooling system. Check that the ignition is off.

2. The coolant temperature sensor is located on the upper left side of the cylinder head.

3. Disconnect the electrical connector from the coolant temperature sensor.

4. Unscrew the sensor and remove the sealing ring.

Installation

1. Installation is performed in the reverse order of removal. Add coolant to the cooling system.

Electromagnetic actuator elr

Removal

1. The ARA solenoid actuator is bolted to the rear of the high pressure fuel pump. On vehicles equipped with Electronic Idle Speed Control (ELR) and the ARA anti-knock control system, the solenoid actuator is located at the bottom.

2. Remove the ground cable from the battery.

3. On non-turbocharged models, remove the air filter.

4. Disconnect the electrical connector from the actuator.

5. Remove the two bolts and actuator housing from the rear of the high pressure fuel pump. Remove the sealing ring and push rod.

Installation

1. Installation is performed in the reverse order of removal. When installing the actuator, install a new sealing ring. When installing a new actuator, remove the pusher from the old actuator and install it on the new actuator.

Exhaust Gas Recirculation System Vacuum Valve

See the corresponding description in subsection 13.6.

Air flow meter

Removal

1. Remove the ground cable from the battery. Remove the air filter.

2. Unscrew the air filter bracket from the air flow meter housing.

3. Loosen the clamps and remove the air ducts from the air flow meter. Remove the O-rings.

4. Disconnect the electrical connector from the air flow meter.

5. Remove the nuts and bolts and remove the air flow meter from the bracket.