Introduction
The engine control system on the diavel uses a sensor that measures air temperature. This sensor has a resistance of ntc type (negative temperature coefficient), that reduces its own value when the temperature increases. The air temperature sensor allows the engine control unit to modify the fuel-air mixture and ignition advance in relation to the atmospheric air temperature.
Components assembling position

The air temperature sensor is mounted on the right hand air intake (the image also shows the location of the connection).
Wiring diagram

Ccm engine control connection, s air temperature sensor. 1 Green/blue - g/b, 2 black/purple - bk/v.
In the event of fault
In the event of an air temperature sensor fault, the engine control unit implements a recovery value of 25C.
Fault codes generated and possible correlated faults
Fault codes generated by the engine control unit and displayed by the dds (intake air temperature sensor diagnosis):
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 - short-circuit to ground = with the battery cables disconnected, using an ohmmeter, continuity is detected 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 "air temperature" 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), the engine does not start easily. Check: -sensor resistance, which must be approximately 2 kohm at 25 C.
The air temperature value may be checked using the dds. Check that the value given is plausible.
If none of the aforementioned tests identify the problem and the air temperature sensor is in proper working order, replace the engine control unit.
Component replacement methods
No special measures are necessary in order to replace the air temperature sensor.
Component assembling position
Engine temperature sensorIndicator cons. Avg - average fuel consumption
This function indicates the "average" fuel consumption.
The calculation is made considering the quantity of fuel used and
the km travelled since the last trip 1 reset. When trip 1 is reset,
the value is set to zero and the first available value is shown on
the display 10 seconds afte ...
Refitting the rear footrests
Note
The refitting of the rear footrests is described for the right side but it
is the same for both.
If previously removed, refit the rubber footrest (11) on the rear rh footrest
(6), by pushing it until pad (b) engages in the
other side.
Note
The rubber footrest (11) side featuring the le ...
Indication of range reached for service
When service coupon threshold is achieved, upon every key-
on the system displays the indication of the type of
intervention that is required (oil service or desmo
service).
The (red) warning is activated as a large icon for 10 seconds
upon every key-on (1, fig. 33) Then as a small warning th ...