P0340
DTC P0340 CAMSHAFT POSITION SENSOR CIRCUIT MALFUNCTIONComponent Location:
GENERAL DESCRIPTION
The Camshaft Position Sensor (CM PS) is a sensor that detects the compression TDC of the NO.1 cylinder. The CMPS consists of a hall type sensor and a target on the end of the intake camshaft. When the target triggers the sensor, the sensor voltage is 12 V. If not, the sensor voltage is 0 V. These CMPS signal is sent to the PCM and the PCM uses the CMPS signal for synchronizing the firing of sequential fuel injectors.
DTC DESCRIPTION
The PCM monitors the camshaft sensor signal transition position which must change only once per crankshaft revolution. If no camshaft signal is detected while crankshaft signal is detected, the PCM sets DTC P0340.If same error code is set in the next driving cycle, the PCM illuminates the MIL.
DTC Detecting Condition:
Specification:
Schematic Diagram:
SIGNAL WAVEFORM & DATA
This figure shows the wave form measured at terminal 2 of CMPS.
1. Make sure there is any missing tooth or noise while changing RPM.
2. The wave form must be displayed regularly.
3. HI level at point (1) should be over 12 V and LOW level at point � should be below 0.6 V.
The given data is the normal waveform of the Crankshaft Position Sensor (CKPS) and Camshaft Position Sensor (CMPS). The left picture is at idle and the right picture is at 2500 rpm. The PCM controls the injection timing and the ignition timing by using these signals. The CKPS signal is used to detect the piston's position and the CMPS signal is used to detect the compression Top Dead Center of each cylinder.
MONITOR DTC STATUS
This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.
1. Engine "ON"
2. Monitor wave form at the terminal 2 of CMPS.
3. Is parameter displayed within specifications'?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO: Go to "W/Harness Inspection" procedure
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of vehicle Repair" procedure.
NO: Go to "Power circuit inspection" procedure.
POWER CIRCUIT INSPECTION
After disconnecting CMPS connector,checking power line is for finding open circuit in CMPS wiring.
1. Ignition "OFF".
2. Disconnect CMP sensor connector.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between terminal 1 of sensor harness connector and chassis ground.
Specification : approximately B+
5. Is measure voltage within Specification?
YES: Go to "Signal circuit inspection" procedure.
NO:
- Open or short circuit to chassis ground between CMPS harness connector and battery power circuit.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure
NOTE: In case, when CMPS connector is disconnected, the voltage at terminal us 0 V
- Possible cause: Open or shod circuit between I/P-J/BOX fuse(15 A) and CMPS terminal 1.
SIGNAL CIRCUIT INSPECTION
After disconnecting CMPS connector,the measurement of CMPS signal voltage is for finding open or short circuit by checking the pull-up voltage from PCM.
1. Check for open in harness
1. Ignition "OFF'
2. Disconnect CMP sensor connector.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between terminal 2 of sensor harness connector and chassis ground.
Specification : approximately 12 V
5. Is measure voltage within Specification?
YES: Go to "Check for short to power in harness" as below.
NO:
- Open or short circuit between CMPS harness connector and PCM harness connector.
- Fault PCM
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure
NOTE: In case,when CMPS connector is disconnected,the voltage at terminal 2 is 0 V.
- Possible cause Open signal line or faulty PCM
2. Check for short to ground in harness
1. Ignition "OFF"
2. Disconnect CMP sensor connector and PCM connector.
3. Ignition "ON" & Engine "OFF"
4. Measure resistance between terminal 2 and 3 of sensor harness connector.
Specification : infinite
5. Is measure resistance within Specification?
YES: Go to "Ground Circuit Inspection" procedure.
NO:
- Short circuit to ground between CMPS harness connector and PCM harness connector.
- Short circuit between CMPS signal circuit and ground circuit.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure
3. Check for short to power in harness
1. Ignition "OFF"
2. Disconnect CMP sensor connector and PCM connector.
3. Ignition "ON" & Engine "OFF"
4. Measure resistance between terminal 1 and 2 of sensor harness connector.
Specification: infinite
5. Is measure resistance within Specification?
YES: Go to "Ground Circuit Inspection" procedure.
NO:
- Short circuit between CMPS signal circuit and power circuit.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure
GROUND CIRCUIT INSPECTION
1. Ignition "OFF"
2. Disconnect CMP sensor connector.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage or resistance between terminal 3 of sensor harness connector and chassis ground.
Specification : below 0.5 V or below 1 Ohms
5. Is measure voltage or resistance within Specification?
YES: Go to "Component Inspection" procedure.
NO:
- Open circuit between Fuel sender harness connector and chassis ground.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all rediness test have been verified as "Complete"
5. Are any DTCs present?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.