P0340
DTC P0340 CAMSHAFT POSITION SENSOR A CIRCUIT MALFUNCTION (BANK 1 OR SINGLE SENSOR)Component Location:
GENERAL DESCRIPTION
Camshaft Position Sensor (CMPS) is a hall sensor and detects the camshaft position by using a hall element. It is related with Crankshaft Position Sensor (CKPS) and detects the piston position of the each cylinder which the CKPS can't detect. The two CMPS are installed on engine head cover of bank 1 and 2 and uses a target wheel installed on the camshaft. This sensor has a hall-effect IC which output voltage changes when magnetic field is made on the IC with current flow. When teeth on the target wheel trigger the sensor, output voltage is 5 V. If not, it is 0 V. These CMPS signal is sent to the PCM and it uses CMPS signals for determining the ignition timing with CKPS signals. CMPS makes Sequential Injection possible.
DTC DESCRIPTION
If signals from CMPS is not synchronized with CKPS for more than 3 times under detecting condition, PCM sets P0340. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition:
Schematic Diagram:
Signal Waveform And Data:
SIGNAL WAVEFORM AND DATA
This example shows a typical Crankshaft Position Sensor (CKPS) and Camshaft Position Sensor (CMPS) waveform at idle. The PCM controls the injection and ignition timing by using these signals. Generally CKPS signal is used to detect the piston's position and CMPS signal is used to detect the Top Dead Center of each cylinder.
MONITOR SCANTOOL DATA
1. IG "OFF" & connect Scantool.
2. ENG "ON" and warm -up the engine to normal operating temperature.
3. Monitor items related to CMPS on the service data.
4. Is the service data displayed correctly?
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, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure
NO: Go to "Terminal and Connector Inspection" procedure
TERMINAL AND 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
1. IG "OFF" and disconnect CMPS connector.
2. IG "ON" and ENG "OFF"
3. Measure voltage between terminal 1 of CMPS(B1) harness connector and chassis ground.
Specification : Approx.5 V
4. Is the measured voltage within specification?
YES: Go to "Signal Circuit Inspection" procedure.
NO: Repair open or short to ground in harness, and go to "Verification of Vehicle Repair" procedure.
SIGNAL CIRCUIT INSPECTION
1. Check voltage
1. IG "OFF" and disconnect CMPS connector.
2. IG "ON" and ENG "OFF"
3. Measure voltage between terminal 3 of CMPS(B1) harness connector and chassis ground.
Specification : Approx.5 V
4. Is the measured voltage within specification?
YES: Go to "Component Inspection" as follows.
NO: Go to "Check open in harness" as follows.
2. Check open in harness
1. IG "OFF" and disconnect CMPS connector and PCM connector.
2. Measure resistance between terminal 3 of CMPS harness connector and terminal 25 of PCM harness connector.
Specification : Below 1 Ohm
3. Is the measured resistance within specification?
YES: Go to "Ground Circuit Inspection" procedure.
NO: Repair open in harness, and go to "Verification of Vehicle Repair" procedure.
GROUND CIRCUIT INSPECTION
1. IG "OFF" and disconnect CMPS connector.
2. Measure voltage between terminal 3 of CMPS harness connector and chassis ground.
3. Measure voltage between terminals 2 and 3 of CMPS harness connector.
Specification Measurement "A" - Measurement "B" = Approx. below 200mV
4. Is the measured voltage within specification?
YES: Go to "Component Inspection" procedure.
NO: Repair open or contact resistance in harness, and go to "Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check CMPS
1. IG "OFF" and connect Scantool.
2. ENG "ON" and Measure signal waveform at terminal 3 of CMPS.
3. Is the measured signal waveform normal?
YES: Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NO: Substitute with a known - good CMPS and check for proper operation. If the problem is corrected, replace CMPS and go to "Verification of Vehicle Repair" procedure.
NOTE: There is a memory reset function on Scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others
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 readiness tests have been verified as "Complete"
5. Are any DTCs present?
YES: Go to the applicable trouble shooting procedure.
NO: System is performing to specification at this time.