|  |  | Results of the tests | 
| 0 | PRELIMINARY CHECKS | All OK | Problems met | Operation | 
|---|
|  | Check
the condition of the compressor drive belt | Continue to Step 1 | Tension incorrect | Replace the belt  Op.   1092G10 | 
| Deteriorated belt. | Replace the belt  Op.   1092G10 | 
| 1 | CHECKING  WITH DIAGNOSTIC EQUIPMENT | All OK | Problems met | Operation | 
|---|
|  | Connect
the diagnostic equipment (Examiner) to the diagnostic socket.Check that there are no faults in the engine management control
unitCheck that there are no faults in the climate control control
unit | Continue to Step 2 | An error is detected in
the control unit | Continue following the instructions for the diagnostic
equipment | 
| An error is detected in climate control unit | Continue following the instructions for the diagnostic
equipment | 
| Lack of communication with the climate control system
control unit (CAN line error) | Restore connection between climate control system control unit
and body computer connector  See   E6020  AIR CONDITIONING | 
| 2 | ACTIVE DIAGNOSIS WITH DIAGNOSTIC
EQUIPMENT | All
OK | Problems
met | Operation | 
|---|
|  | Using
the diagnostic equipment (Examiner or other instruments) carry out
active diagnosis on compressor activation relay operation | Continue to Step 3 | Compressor relay faulty | Replace the relay | 
| Connections not correct | Restore the connection between engine management control unit,
relay and compressor coupling as on the wiring diagram  See   E6021  COMPRESSOR ENGAGEMENT | 
| 3 | CHECK COMPRESSOR ACTIVATION ELECTRICAL
CIRCUIT | All
OK | Problems
met | Operation | 
|---|
|  | Check
the operation of the compressor electro-magnet coupling. | Continue to Step 4 | Connections not correct | Restore the connections
between the climate control unit, pressure switch and control unit
as on the wiring diagram  See   E6021  COMPRESSOR ENGAGEMENT | 
| Pressure switch defective | Replace the pressure switch  Op.   5040B14 | 
| 4 | CHECK COMPRESSOR ELECTRO-MAGNET
COUPLING | All
OK | Problems
met | Operation | 
|---|
|  | Check, in order: | Continue to Step 5 | Defective compressor coupling | Replace the compressor
complete with coupling   Op.   5040A34 | 
| 5 | CHECKING SYSTEM PRESSURE | All OK | Problems met | Operation | 
|---|
|  | Checking
system pressures: | Continue to Step 6 | High pressure does not
increase or low pressure decreases too much: leaks in the circuit | Locate the leaks and restore
the correct operation. | 
| High pressure continues to rise: the compressor cooling
fan does not cut in | If the fault is  associated with that of excessive engine
heating See table D30 ENGINE OVERHEATING | 
| 6 | CHECKING EVAPORATOR | All OK | Problems met | Operation | 
|---|
|  | Check
high and low pressure pipe for leaks, and condition of evaporator | Continue to Step 7 | Pipe from compressor to condenser damaged | Replace the pipe  Op.   5040A50 | 
| Pipe from filter to evaporator damaged | Replace the pipe  Op.   5040A64 | 
| Evaporator dirty | Replace the evaporator  Op.   5040C10 | 
| 7 | CHECK ON CORRECT OPERATION | All OK | Problems met | Operation | 
|---|
|  | Check
that the fault is no longer present |  | Fault persists | Search for the fault starting from another symptom' |