Code No. P0340: Inlet Camshaft Position Sensor System


OPERATION



  • Output signal is supplied to the engine-ECU connector terminal CPI from the crank angle sensor connector terminal and is earthed to the engine-ECU connector terminal CPIE from the crank angle sensor connector terminal.
  • A power voltage of 5 V is applied to the inlet camshaft position sensor output terminal connector terminal from the engine-ECU connector terminal 5V.

FUNCTION



  • The inlet camshaft position sensor detects the position of the inlet camshaft and inputs the pulse signal to the engine-ECU.
  • In response to the inlet camshaft position sensor signal and the crank angle sensor signal, the engine-ECU detects the compression top dead centre of the No. 1 cylinder.
  • Also, in response to the inlet camshaft position sensor signal, the engine-ECU controls variable valve timing (V.V.T.).

TROUBLE JUDGMENT


Check Condition, Judgment Criterion
  • Normal signal pattern has not been input for cylinder identification from the crank angle sensor signal and inlet camshaft position sensor signal for 2 seconds.
Check Condition
  • Engine is being cranked.
Judgement Criterion
  • Inlet camshaft position sensor output voltage has not changed (no pulse signal is input) for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION



  • Engine runs is learned pattern until engine stops.
  • Does not control variable valve timing (V.V.T.).

PROBABLE CAUSES



  • Failed inlet camshaft position sensor
  • Open/short circuit or harness damage in inlet camshaft position sensor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Perform voltage measurement at inlet camshaft position sensor connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: "ON"
  • Voltage between terminal engine-ECU 5V line and body earth.
OK: 4.9 - 5.1 V

Q. Is the check result normal?
Go to Step 4.
Go to Step 2.

STEP 2. Check harness between inlet camshaft position sensor connector terminal and engine-ECU connector terminal 5V.

  • Check power supply line for open/short circuit.

Q. Is the check result normal?
Go to Step 3.
Repair or replace the connector, or repair the damaged harness wire.

STEP 3. M.U.T.-III diagnosis code

  • Reconfirmation of diagnosis code.

Q. Is the diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 4. Perform voltage measurement at inlet camshaft position sensor connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: "ON"
  • Voltage between terminal engine-ECU CPI line and body earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 6.
Go to Step 5.

STEP 5. Check harness between inlet camshaft position sensor connector terminal and engine-ECU connector terminal CPI.

  • Check output line for open/short circuit.

Q. Is the check result normal?
Go to Step 3.
Repair or replace the connector, or repair the damaged harness wire.

STEP 6. Perform resistance measurement at inlet camshaft position sensor connector.

  • Disconnect connector, and measure at harness side.
  • Resistance between terminal engine-ECU CPIE line and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 8.
Go to Step 7.

STEP 7. Check harness between inlet camshaft position sensor connector terminal and engine-ECU connector terminal CPIE.

  • Check earthing line for open circuit and damage.

Q. Is the check result normal?
Go to Step 3.
Repair or replace the connector, or repair the damaged harness wire.

STEP 8. Perform output wave pattern measurement at inlet camshaft position sensor connector (Using an oscilloscope).

  • Use special tool test harness (MB991709) to connect connector, and measure at pick-up harness.
  • Engine: Idling
  • Transmission: P range
  • Voltage between terminal engine-ECU 5V line and body earth.
OK: Waveforms should be displayed on inspection procedure using an oscilloscope (Refer to ), its maximum value should be 4.8 V or more, and its minimum value should be 0.6 V or less. There must be no noise in the output wave pattern.

Q. Is the check result normal?
Go to Step 3.
Go to Step 9.

STEP 9. Check harness between inlet camshaft position sensor connector terminal and engine-ECU connector terminal 5V.

  • Check power supply line for damage.

Q. Is the check result normal?
Go to Step 10.
Repair or replace the connector, or repair the damaged harness wire.

STEP 10. Check harness between inlet camshaft position sensor connector terminal and engine-ECU connector terminal CPI.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 11.
Repair the damaged harness wire.

STEP 11. Check intake camshaft sensing position.

Q. Is the check result normal?
Go to Step 12.
Replace the intake camshaft.

STEP 12. M.U.T.-III diagnosis code

  • Reconfirmation of diagnosis code.

Q. Is the diagnosis code set?
Replace the inlet camshaft position sensor.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).