NO SIGNAL
Test results
1
ELECTRICAL CONNECTIONS CHECK
All OK
Problems encountered
Operation
Check for loose electrical connections at the sensor connector and at the engine management control unit.
Go to Step 2
Presence of loose electrical connections.
Restore the correct connections.
2
WIRING CONTINUITY CHECK
Check for breaks in the wiring continuity
See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
Go to Step 3
Breaks in the wiring continuity.
Restore the correct continuity for the wiring.
3
WIRING INSULATION CHECK
Check the condition of the wiring insulation (check for inversion of signal leads or open circuit at signal leads).
Go to Step 4
Wiring insulation faulty.
Restore correct wiring insulation.
4
EARTH CONNECTIONS CHECK
Check the condition of the earth connections.
Go to Step 5
Restore the correct earth connections.
5
CHECK ON SEEPAGE IN EXHAUST MANIFOLD
Check for the presence of any seepage in the exhaust manifold.
Go to Step 6
Seepage inside the exhaust manifold.
Restore correct operation
6
SENSOR CONDITION CHECK
Check for the presence of any oil or oxidation on the sensitive element or impact to the sensor casing. Also check that it is correctly fitted.
Go to Step 7
Sensor fouled, contaminated or not correctly installed.
Clean the sensor or fit it correctly.
7
LAMBDA SENSOR OPERATION CHECK
Check that the Lambda sensor is working properly by performing the
See Test 1080BA Check on the operation of the upstream Lambda sensor
Go to Step 8
Lambda sensor not working properly.
Replace the Lambda sensor
Op. 1080B94 FRONT LAMBDA SENSOR TO WITH CATALYTIC CONVERTER - R.R
8
ENGINE MANAGEMENT CONTROL UNIT OPERATION CHECK
Check that the engine management control unit is working properly.
End of diagnosis
Engine management control unit faulty.
Replace the engine management control unit
Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R
SIGNAL NOT VALID
Check the condition of the wiring insulation (check for inversion of signal leads or short circuit between signal leads).
ABOVE THRESHOLD
Check the condition of the wiring insulation (check for inversion of signal leads or short circuit to Vbatt).
BELOW THRESHOLD
Check the condition of the wiring insulation (check for inversion of signal leads or short circuit to GND).