Dacia SuperNova (engine E7J). Service manual — part 31

E7J-A-2/60 ENGINE

17

IGNITION AND INJECTION

17 - 34

DIAGNOSING-INTERPRETING THE DEFECTS

DEFECT
PRESENTOR
MEMORIZED

WATER TEMPERATURE SENSOR CIRCUIT

Breakdown of water temperature sensor

Conditions of breakdown detection by the calculator:
-set the contact
-if the defect is only memorized, start the engine and keep it run till
the first start of the cooling engine ventilator.
Conditions of performing the diagnosing:
-the defect is present
-the defect has been memorized but is recorded in the “present” state.

SUGESTIONS

Check the connection and the state of the water temperature sensor
Change the connector if necessary.

Check that the resistance of the water temperature sensor is not 0 or “infinite” (i.e. certain
breakdown of the sensor).
Change the sensor if necessary.

Connect the 90-way terminal-tester instead of the calculator and check the insulation,
the continuity and the absence of contact resistance along the circuits:
pin 73 of calculator

♦

pin B1 of the water temperature sensor

pin 13 of calculator

♦

pin B2 of the water temperature sensor.

Remedy if necessary.

Check that the alteration of the resistance of the sensor for various temperatures is in
keeping with its variation curve.
Change the sensor if necessary.

The problem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an

electric shock.
The cause of the destruction must be found before mounting a new
calculator.

Erase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.

AFTER REPAIR

18.

E7J-A-2/60 ENGINE

17

IGNITION AND INJECTION

17 - 35

DIAGNOSING-INTERPRETING THE DEFECTS

AIR TEMPERATURE SENSOR CIRCUIT

Breakdown of air temperature sensor

DEFECT
PRESENTOR
MEMORIZED

Conditions of breakdown detection by the calculator:
-set the contact
-if the defect is only memorized, start the engine and keep it run till
the first start of the cooling engine ventilator.
Conditions of performing the diagnosing:
-defect is present
-the defect has been memorized but is recorded in the “present” state.

SUGGESTIONS

Check the connection and the condition of the air temperature sensor
Change the connector if necessary.

Check that its resistance is not 0 (i..e. certain breakdown).
Remedy the sensor if necessary.

Connect the 90-way terminal-tester instead of the calculator and check the insulation,
the continuity and the absence of contact resistance along the circuits:
pin 77 of calculator

♦

pin 2 of air temperature sensor

pin 49 of calculator

♦

pin 1 of air temperature sensor.

Remedy if necessary.

Check that the alteration of the resistance of the air temperature sensor for various tem-
peratures is in keeping with its variation curve.

The problem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an

electric shock.
The cause of the destruction must be found before mounting a new
calculator.

Erase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.

AFTER REPAIR

19.

E7J-A-2/60 ENGINE

17

IGNITION AND INJECTION

17 - 36

DIAGNOSING-INTERPRETING THE DEFECTS

DEFECT
PRESENT

CANISTER DRAINING VALVE CIRCUIT
1. Short-circuit at 12 V along the way to pin 4 of calculator

(draining valve command)

2. Short-circuit at mass along the way to pin 4 of calculator

(draining valve command)

3. Open circuit along the way to pin 4 of calculator (draining valve
command)

20.

SUGGESTIONS

Check the connection and the condition of the canister draining valve connector
Change the connector if necessary.

Check the resistance of draining valve.
Change the valve if necessary.

Check, after setting the contact, the presence of +12V at pin 1 of the canister draining
valve.
Remedy if necessary.

Connect the 90-way terminal-tester instead of the calculator and check the insulation and
the continuity along the circuit:
pin 4 of calculator

♦ pin 2 of canister draining valve

Remedy if necessary.

Change canister draining valve

The problem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an

electric shock.
The cause of the destruction must be found before mounting a new
calculator.

Erase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.

AFTER REPAIR

E7J-A-2/60 ENGINE

17

IGNITION AND INJECTION

17 - 37

DIAGNOSING-INTERPRETING THE DEFECTS

DEFECT
PRESENTOR
MEMORIZED

OXYGEN PROBE CIRCUIT

Breakdown of oxygen probe signal

Conditions of breakdown detection by the calculator:
-set the contact
-start the engine and wait for the enrichment adjustment to be
active for at least 5 minutes.
Conditions of performing the diagnosing:
-defect is present
-the defect has been memorized but is recorded in the “present” state.

SUGGESTIONS

Check the connection and the condition of the oxygen probe
Change the connector if necessary.

Check if there is any “false air” caused by cases of lack of watertightness along the
exhaust-probe circuit.

If the car has been running a lot out of town proceed to probe-cleaning

Check, after setting the contact, the presence of +12 V at pin A of the oxygen probe.
Remedy if necessary

Connect the 90-way terminal-tester instead of the calculator and check the insulation,
the continuity and the absence of contact resistance along the circuits:
pin 45 of calculator

♦

pin C of oxygen probe

pin 80 of calculator

♦

pin D of oxygen probe.

Remedy if necessary.

Change the oxygen probe if the incident persists

The problem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an

electric shock.
The cause of the destruction must be found before mounting a new
calculator.

Erase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.

AFTER REPAIR

21.