P0338
DTC P0338 CRANKSHAFT POSITION SENSOR A CIRCUIT HIGH INPUTComponent Location:
COMPONENT LOCATION
GENERAL DESCRIPTION
The Crankshaft Position Sensor (CKPS) is a hall effect type sensor that generates voltage using a sensor and a target wheel mounted on the crankshaft. When the slot in the wheel aligns with the sensor, the sensor voltage outputs low. When the metal (tooth) in the wheel aligns with the sensor, the sensor voltage outputs high. The PCM calculates engine RPM by using the sensor's signal and controls the injection duration and the ignition timing. The engine will stop if the signals from the sensor to the PCM are lost.
DTC DESCRIPTION
If the output voltage of CKPS & CMPS is satisfied with the threshold value, the PCM determines that a fault exists and a DTC is stored.
DTC Detecting Condition:
Signal Waveform:
Schematic Diagram:
MONITOR SCANTOOL DATA
1. Ignition "ON" & Engine "ON"
2. Monitor "Engine Speed(RPM)" parameter on scantool.
NOTE: Scantool provides "Engine Speed(RPM)" parameter for CKPS.
3. Does the "Engine Speed(RPM)" on scantool coincide with "Engine Speed(RPM)" on instrument board each other?
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 go to "Verification 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 Signal Circuit Inspection" procedure.
SIGNAL CIRCUIT INSPECTION
1. Check voltage
1. Ignition "OFF"
2. Disconnect CKPS connector
3. Ignition "ON". & Engine "OFF"
4. Measure voltage between terminal "2" of CKPS harness connector and chassis ground.
Specification: 5 V
5. Is the measured voltage within specifications?
YES: Go to" Ground Circuit Inspection " procedure.
NO: Go to "Check for short to battery in harness" as below.
2. Check for short to battery in harness
1. Ignition "OFF"
2. Disconnect CKPS connector.
3. Measure resistance between terminals "2" and "3" of CKPS harness connector.
Specification: Infinite
4. Is the measured resistance within specifications?
YES: Go to "Check for open in harness "as below.
NO:
- Check short to battery in signal harness.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
3. Check for open in harness
1. Ignition "OFF"
2. Disconnect CKPS and PCM connector.
3. Measure resistance between terminal "2" of CKPS harness connector and terminal "5" of PCM harness connector.
Specification: Approx. below 1 Ohms
4. Is the measured resistance within specifications?
YES: Go to "Ground Circuit Inspection" procedure.
NO:
- Check open in harness between CKPS connector and PCM connector.
- Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
GROUND CIRCUIT INSPECTION
1. Check for open in harness
1. Ignition "OFF"
2. Disconnect CKPS connector.
3. Measure resistance between terminal "1" of CKPS harness connector and chassis ground.
Specification: Approx. below 1 Ohms
4. Is the measured resistance within specifications?
YES: Go to "Component Inspection" procedure.
NO:
- Check open in harness.
- Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check CKPS
1. Connect CKPS and PCM connector.
2. Engine "ON"
3. Check the signal waveform of CKPS on scantool.
Specification: Check whether the waveform is synchronized with Camshaft Position Sensor or not.
4. Is the signal waveform normal?
YES: Go to "Check PCM" as below.
NO:
- Substitute with a known good CKPS and check for proper operation.
- If the problem is corrected, replace CKPS and go to "Verification of Vehicle Repair" procedure.
2. Check PCM
1. Ignition "OFF" & Engine "OFF"
2. Connect Scantool and Ignition "ON" & Engine "OFF"
3. Disconnect CKPS connector and Select simulation function on scantool.
4. Simulate voltage at terminal "2" of CKPS harness connector.
5. Does the signal value of CKPS changes according to simulation voltage?
YES:
- Thoroughly check connectors for looseness, poor connection, bending,corrosion, contamination, deterioration, or damage.
- Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO:
- 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.
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 troubleshooting procedure.
NO: System is performing to specification at this time.