P1396

CRANKSHAFT POSITION SENSOR





Fault Symptoms
The engine fails to start or misfires.
Other diagnostic trouble codes (misfiring).

Conditions.
P0335
No voltage signal from the crankshaft position sensor even though the camshaft position sensor has detected 8 crankshaft revolutions.

P0336
^ Engine speed above 500 rpm.
^ Gap not found in slotted ring which is missing two ribs.

P1396
^ Engine speed above 500 rpm.
^ One "rib" too many detected on the slotted ring.

Diagnostic Help.
The diagnostic trouble code may be generated if the slotted ring mounted on the crankshaft is damaged, as might happen in connection with work carried out on the basic engine.

Check The Wiring.
Intermittent faults may occur as a result of temporary short circuits and breaks in the wiring. Jiggle the wiring at several points and in different directions to ascertain whether the wiring harness, including any connectors, is causing the trouble. Observe the multimeter, ISAT scan tool or test lamp while doing this.





Diagnostic Procedure.
1. Check the resistance of the crankshaft position sensor

- Unplug the crankshaft position sensor's 4-pin connector.
- Take a resistance reading on the contacts of the sensor's connector:
^ pins 1 - 2: 860 ± 90 ohm.
- Check for possible stray currents between the signal lead and the screened lead. Take readings across pins 1 and 3.

Nominal resistance is infinite (OL = OverLoad).

Are the resistance readings OK?

YES: Continue with point 2.
NO: Change the crankshaft position sensor and continue with point 5.





2. Check the mounting of the crankshaft position sensor

- Remove the crankshaft position sensor and check:
^ that the sensor tip is not soiled with metal filings, swarf, etc.
^ that the slotted ring is firmly secured to the crankshaft (by prising it gently with a screwdriver).
^ while rotating the crankshaft, that the slotted ring is not skew, buckled or otherwise damaged.
- Brush any metal filings, etc. off the sensor.

Is the slotted ring damaged or insecurely mounted?

YES: Check the Basic engine.
NO: Continue with point 3.





3. Check the crankshaft position sensor's ground and screened connection
- Connect the test lamp to the connector between:
^ Battery positive (B+) and pin 2.
^ Battery positive (B+) and pin 3.

Did the test lamp light up in both cases?

YES: Continue with point 4.
NO: Check and if necessary repair or replace the relevant lead between:
^ pin 2 and control module pin 20
^ pin 3 and crimped connection J135.
Then continue with point 5.





4. Check the control module's sensor Input

- Turn the ignition switch to the ON position.
- Take voltage readings on the connector.
^ pin 1 to battery negative (B-): about 0.9 V.

Is the lead OK?
YES: Change the crankshaft position sensor and then continue with point 5.
NO: Repair or replace the lead and then continue with point 5.





5. Final check

- Clear the diagnostic trouble code.
- Implementation of driving cycle:
^ Drive the car at varying engine loads and rpm for 5 minutes.
- Evaluation of driving cycle:
^ Check whether the diagnostic trouble code has recurred.

Has the diagnostic trouble code recurred?
YES: Continue at "Before replacing a Control Module". Component Tests and General Diagnostics
NO: The steps taken to rectify the fault were correct.