Двигатели Scania четвёртой серии. Руководство — часть 158

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03:04-06

Fault code D101

Fault

The voltage has been below 0.147 V (under -
1.2 bar absolute pressure), i.e. below the lower
limit for the fuel pressure to the front bank,
cylinder 1-3.

Cause

The voltage between pin 3 and 2 in connector
A1 is too low, or there is a fault with the
voltage supply to sensor group 2 (pin 8 in
connector B2, pin 1 in connector A1).

Remarks

If the voltage is outside the permitted range, the
control unit uses a pre-programmed value
(0.448 bar absolute pressure).

If the value from the fuel pressure sensor for
the rear bank, cylinder 4-6 is incorrect at the
same time, it is probably the shared voltage
supply for the sensors which is faulty.

Engine torque is limited by approximately 30%
as long as the fault is active.

Action

Check the signal from the fuel pressure sensor.

Check for any visible faults on the sensor and
the wiring.

Clean the connectors.

Then, erase the fault code memory and check
whether the fault code is generated again.

Fault codes

03:04-06

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71

Fault code D102

Fault

Internal fault in the control unit.

Cause

The control unit could not process (convert) the
signal from the fuel pressure sensor on the
front bank, cylinder 1-3.

Remarks

If the fault is active, the control unit uses a pre-
programmed value (0.448 bar absolute
pressure).

Engine torque is limited by approximately 30%
as long as the fault is active.

Action

Clear the fault code memory. Start the engine
and accelerate the engine to full speed.

If the fault code is regenerated, renew the
control unit.

Fault codes

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03:04-06

Fault code D103

Fault

The fuel pressure to one or two cylinders in the
front bank, cylinder 1-3, is too high.

Cause

The control unit has discovered that the
pressure from the solenoid valve to the injector
does not drop as expected due to an obstruction
in the fuel supply to the injector.

The fault code can be generated if the vehicle
has not been driven for some time, especially in
cold weather, as air might have entered the
system. The fault code will be generated, either
when starting or within two minutes after
starting.

Remarks

As a result, the engine is running unevenly due
to no fuel supply to one or two cylinder.

Action

Bleed the fuel system and bring the engine to
operating temperature.

If the engine runs unevenly despite bleeding
the fuel system and bringing the engine to
operating temperature, carry out the following:

Change injectors on the front bank, cylinder
1-3.

Clean the fuel rail (clean the ducts for injection
timing and fuel with compressed air).

Clean the fuel ducts in the cylinder heads on
the front bank, cylinder 1-3.

If it becomes evident that the fault is due to
debris in the fuel system, check the fuel filter
and change if necessary.

Fault codes

03:04-06

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73

Fault code D104

Fault

The fuel pressure to all cylinders in the front
bank, cylinder 1-3, is too high.

Cause

The fuel volume solenoid valve may be stuck
open.

The fuel pressure sensor signal is incorrectly
high in relation to the expectation of the control
unit considering the current engine load.

Remarks

As a result, the engine speed is limited to
between 500 and 550 rpm by means of the fuel
shut-off valve. The engine runs very unevenly.

Action

Check the wiring and clean the connectors to
the solenoid valves and the pressure sensor on
the front bank, cylinder 1-3.

Clear the fault code memory. Start the engine
and accelerate the engine to full speed.

If the fault remains, first renew the fuel volume
solenoid valve and if necessary the fuel
pressure sensor.

Fault codes