Ducati Diavel Service Manual: Absolute pressure sensors

Introduction

The engine control system of the diavel is equipped with two absolute pressure sensors, with one connected to the intake duct of each cylinder (map 1 cylinder 1 - horizontal - map 2 cylinder 2 - vertical). They are used by the control unit to determine the quantity of fuel to be injected according to the speed-density strategy and to determine the atmospheric pressure (necessary information to correct the carburation in accordance with the altimetric measurement).

Components assembling position

The absolute pressure sensors of the vertical (1) and horizontal (2) cylinders are fixed near the airbox (the image shows also the position of the sensor connection).

Wiring diagram

O absolute pressure sensor 1, horizontal cylinder. Ccm engine control connection, 1 ground, black/purple - bk/v, 2 power (5v), brown/purple - bn/v, 3 signal generated, green/white - g/w.

V absolute pressure sensor 2 vertical cylinder. Ccm engine control connection, 1 ground, black/purple - bk/v, 2 power (5v), brown/purple - bn/v, 3 signal generated, green/white - g/w.

In the event of fault

In the event of a fault of absolute pressure sensor 1, the engine control unit uses the information from absolute pressure sensor 2 instead.

In the event of a fault of absolute pressure sensor 2, the engine control unit uses the information from absolute pressure sensor 1 instead.

In the event of a fault of both absolute pressure sensor 1 and absolute pressure sensor 2:

• The engine control unit implements an atmospheric pressure value of 1.013 Bar.
• The fuel quantity injected is determined using the á-n strategy only.

Fault codes generated and possible correlated faults

Fault codes generated by the engine control unit and displayed by the dds (maps 1 sensor diagnosis - maps 2 sensor diagnosis):

• Absolute pressure sensor 1 (cylinder 1 - horizontal) and/or absolute pressure sensor 2 (cylinder 2 - vertical), open circuit: check integrity of electric circuit and electrical connections
• Absolute pressure sensor 1 (cylinder 1 - horizontal) and/or absolute pressure sensor 2 (cylinder 2 - vertical), short circuit to vdc: check integrity of electric circuit and electrical connections
• Absolute pressure sensor 1 (cylinder 1 - horizontal) and/or absolute pressure sensor 2 (cylinder 2 - vertical), short circuit to ground: check integrity of electric circuit and electrical connections

Note

Check integrity of electric circuit - short-circuit to vdc = with dashboard on, using a voltmeter, a voltage is measured between the wire tested and ground.

Check integrity of electric circuit - open circuit = with the battery cables disconnected, using an ohmmeter, no continuity is detected between the two ends of the wire tested.

The dashboard service display shows the error "pressure" and the eobd warning light activates.

Possible correlated faults: inadequate engine power, irregular idle speed (target idle speed is 1350 rpm with engine stabilised at operating temperature). Check:

• That the sensors are connected securely to the intake ducts and check the integrity of the pipe.
• That valve clearance is correct.
• Cylinder compression.
• That there is no anomalous air infiltration into the intake duct.

The dds may be used to read the absolute pressure value within the two intake ducts.

If none of the aforementioned tests identify the problem and the absolute pressure sensors are in proper working order, replace the engine control unit.

Component replacement methods

No special measures are necessary in order to replace absolute pressure sensor 1 and absolute pressure sensor 2, (check integrity of the rubber pipes via which they are connected to the two intake ducts). After replacing one or both of the pressure sensors, reset the self-adaptive parameters relative to carburation with the dds.