Introduction
The radiator fans are powered via a specific relay, which is enabled by the engine control unit.
Component assembling position

A injection relay; b etv relay (throttle valve actuator motor), c radiator fan relay, d engine control unit.

Location of right hand fan connection.

Location of left hand fan connection.
Connection wiring diagram

Ccm engine control connection, t radiator fan relay, a key on power (+15 from hands free relay 30), r battery power (+30), l left hand fan, r right hand fan, 85 light blue/black - lb/bk, 30 red/green - r/g, 86 red/black - r/bk, 87 red/grey - r/gr.
In the event of fault
In the event of a radiator fan relay fault, the radiator fans themselves do not work. The relay is not commanded by the ecu.
Fault codes generated and possible correlated faults fault codes generated by the engine control unit and displayed by the dds (fan relay 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 "fan relay" and the eobd warning light activates.
Possible correlated faults: coolant reaches boiling point but radiator fans not working. Check:
The radiator fan relay may be actuated from the dds to check radiator fan function.
The fans are normally activated at 103 and switched off at 101C.
If none of the aforementioned tests identify the problem and the radiator fan relay is in proper working order, replace the engine control unit.
Component replacement methods
No special measures are necessary in order to replace the radiator fan relay.
Starter motor relay
Engine speed-timing sensorOverhaul of the gearbox
Check the condition of the front coupling dogs of the gears. They must be in
perfect condition and with no sign of wear on
the edges of the teeth.
The idler gears must rotate freely on their shafts.
When refitting, make sure the circlips are correctly positioned.
Check the needle roller ...
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 ...
Overhaul of the crankcase halves
Carefully examine the engine crankcase halves.
Check that the surfaces of the crankcase halves are perfectly flat using a
reference surface.
Check that the bearings (1) and (18), and the bushings (2) and (17) are in
optimum conditions. Note that the main
bearings must always be changed in p ...