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P0340

Camshaft Position Sensor Circuit:




Connectors:






CIRCUIT OPERATION
- The camshaft position sensor power is supplied from the MFI relay (terminal 4).
- Terminal 1 of the camshaft position sensor is grounded with ECM (terminal 40) or PCM (terminal 16) .
- A 5-volt voltage is applied on the camshaft position sensor output terminal (terminal 2) from the ECM (terminal 88) or PCM (terminal 56)
. The camshaft position sensor generates a pulse signal when the output terminal is opened and grounded.

TECHNICAL DESCRIPTION
- The camshaft position sensor functions to detect the top dead center position of the number 1 cylinder and to convert that data to pulse signals that are input to the ECM or PCM
.
- When the engine is running, the camshaft position sensor outputs a pulse signal.
- The ECM or PCM
checks whether pulse signal is input while the engine is cranking.

DTC SET CONDITIONS

Check Conditions
- Engine speed is higher than 50 r/min.

Judgment Criteria
- Camshaft position sensor output voltage has not changed (no pulse signal is input) for 2 seconds.

Check Conditions
- Engine speed is higher than 50 r/min.

Judgment Criteria
- Normal signal pattern has not been input for cylinder identification from the crankshaft position sensor signal and camshaft position sensor signal for 2 seconds.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Camshaft position sensor failed.
- Open or shorted camshaft position sensor circuit, or loose connector.
- ECM failed.
- PCM failed.


DIAGNOSIS

Required Special Tools
- MB991709: Test Harness Set

STEP 1. Using the oscilloscope, check the camshaft position sensor.
1. Disconnect the camshaft position sensor connector B-106, and connect test harness special tool (MB991709) in between. (All terminals should be connected.)




2. Connect the oscilloscope probe to the camshaft position sensor side connector terminal 2.

NOTE: When measuring with the ECM or PCM side connector, connect an oscilloscope probe to terminal 88 or terminal 56
.

3. Start the engine and run at idle.




4. Check the waveform.
- The waveform should show a pattern similar to the illustration.

5. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the waveform normal?

YES: Go to Step 2.

NO: Go to Step 4.




STEP 2. Check connector B-106 at camshaft position sensor for damage.

Q: Is the connector in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.

STEP 3. Check the trouble symptoms.
1. Carry out a test drive with the drive cycle pattern. Refer to, Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code (DTC).

Q: Is the DTC P0340 output?

YES: Replace the ECM or PCM. Then go to Step 20.

NO: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points.




STEP 4. Check connector B-106 at camshaft position sensor for damage.

Q: Is the connector in good condition?

YES: Go to Step 5.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.

STEP 5. Check the sensor supply voltage at camshaft position sensor connector B-106.
1. Disconnect the connector B-106 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal 2 and ground.
- Voltage should be between 4.8 and 5.2 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES: Go to Step 10.

NO: Go to Step 6.

STEP 6. Check the sensor supply voltage at ECM connector C-115 or PCM connector C-118
by backprobing.
1. Do not disconnect the ECM connector C-115 or PCM connector C-118
.
2. Disconnect the camshaft position sensor connector B-106.
3. Turn the ignition switch to the "ON" position.







4. Measure the voltage between terminal 88 or 56
and ground by backprobing.
- Voltage should be between 4.8 and 5.2 volts.

5. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES: Go to Step 7.

NO: Go to Step 8.




STEP 7. Check connector C-115 at ECM or connector C-118 at PCM
for damage.

Q: Is the connector in good condition?

YES: Repair harness wire between camshaft position sensor connector B-106 terminal 2 and ECM connector C-115 terminal 88 or PCM connector C-118 terminal 56
because of open circuit. Then go to Step 20.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.




STEP 8. Check connector C-115 at ECM or connector C-118 at PCM
for damage.

Q:
Is the connector in good condition?

YES: Go to Step 9.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.







STEP 9. Check for short circuit to ground between camshaft position sensor connector B-106 terminal 2 and ECM connector C-115 terminal 88 or PCM connector C-118 terminal 56
.

Q: Is the harness wire in good condition?

YES: Replace the ECM or PCM. Then go to Step 20.

NO: Repair it. Then go to Step 20.

STEP 10. Check the power supply voltage at camshaft position sensor connector B-106.
1. Disconnect the connector B-106 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal 3 and ground.
- Voltage should be battery positive voltage.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES: Go to Step 12.

NO: Go to Step 11.




STEP 11. Check connector B-12X at MFI relay for damage.

Q: Is the connector in good condition?

YES: Repair harness wire between MFI relay connector B-12X terminal 4 and camshaft position sensor connector B-106 terminal 3 because of open circuit or short circuit to ground. Then go to Step 20.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.

STEP 12. Check the continuity at camshaft position sensor connector B-106.
1. Disconnect the connector B-106 and measure at the harness side.




2. Check for the continuity between terminal 1 and ground.
- Should be less than 2 ohm.

Q: Is the continuity normal?

YES: Go to Step 15.

NO: Go to Step 13.




STEP 13. Check connector C-119 at ECM or connector C-120 at PCM
for damage.

Q: Is the connector in good condition?

YES: Go to Step 14.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.







STEP 14. Check for open circuit and harness damage between camshaft position sensor connector B-106 terminal 1 and ECM connector C-119 terminal 40 or PCM connector C-120 terminal 16
.

Q: Is the harness wire in good condition?

YES: Replace the ECM or PCM. Then go to Step 20.

NO: Repair it. Then go to Step 20.




STEP 15. Check connector B-12X at the MFI relay for damage.

Q: Is the connector in good condition?

YES: Go to Step 16.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20.




STEP 16. Check connector C-115 at ECM or connector C-118 at PCM
for damage.

Q: Is the connector in good condition?

YES: Go to Step 17.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 20







STEP 17. Check for harness damage between MFI relay connector B-12X terminal 4 and camshaft position sensor connector B-106 terminal 3.

Q: Is the harness wire in good condition?

YES: Go to Step 18.

NO: Repair it. Then go to Step 20.







STEP 18. Check for harness damage between camshaft position sensor connector B-106 terminal 2 and ECM connector C-115 terminal 88 or PCM connector C-118 terminal 56
.

Q: Is the harness wire in good condition?

YES: Go to Step 19.

NO: Repair it. Then go to Step 20.

STEP 19. Check the camshaft position sensor vane.

Q: Is the vane in a good condition?

YES: Replace the camshaft position sensor. Then go to Step 20.

NO: Repair it. Then go to Step 20.

STEP 20. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to, Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code (DTC).

Q: Is the DTC P0340 output?

YES: Retry the troubleshooting.

NO: The inspection is complete.