| | Test results |
| 1 | WATER TEMPERATURE SENSOR CHECK | All OK | Problems encountered | Operation |
|---|
| Check that the water temperature sensor is working properly by carrying out the See Test 1056BC ENGINE COOLANT TEMPERATURE SENSOR OPERATION CHECK | Move on to Step 4 | Sensor defective | Replace the sensor Op. 1056B50 ENGINE COOLANT TEMPERATURE SENSOR - R + R |
| Sensor wiring connection irregular | Restore the correct connection. |
| 2 | CHECK USING DIAGNOSTIC EQUIPMENT | All OK | Problems encountered | Operation |
|---|
| Connect the Examiner diagnostic equipment to the engine control unit.Check:- that there are no errors in the control unit;- parameter plausibility. | Move on to Step 2 | Error detected in the control unit | Continue following the instructions on the diagnostic equipment |
| Parameters not plausible | Continue following the instructions on the diagnostic equipment |
| 3 | CHECK USING DIAGNOSTIC EQUIPMENT | All OK | Problems encountered | Operation |
|---|
| Connect the Examiner diagnostic equipment to the climate control system control unit.Check:- that there are no errors in the control unit;- parameter plausibility. | Move on to Step 3 | Onset of error detected in the control unit | Continue following the instructions on the diagnostic equipment |
| Parameters not plausible | Continue following the instructions on the diagnostic equipment |
| 4 | WIRING CHECK | All OK | Problems encountered | Operation |
|---|
| Check the continuity of the connections between the engine management control unit and fuse control unitCheck that the fan control relays are working properly See E5020 ENGINE COOLING | Move on to Step 5 | Wiring defective | Restore the correct wiring. |
| Relays defective | Replace the relays |
| 5 | THERMOSTAT CHECK | All OK | Problems encountered | Operation |
|---|
| Check that the thermostat is working properly | Move on to Step 6 | Thermostat defective | Replace the thermostat Op. 1088C40 THERMOSTAT- R + R |
| 6 | ENGINE CONTROL UNIT CHECK | All OK | Problems encountered | Operation |
|---|
| Check that the engine control unit is working properly | End of diagnosis | Engine management control unit defective | Replace the engine management control unit Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R |