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Home >> Jeep >> 2007 >> Wrangler Sahara, Standard >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P0203 To P0420 >> P0340-Camshaft Position Sensor Circuit >> Diagnostic Test
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Diagnostic Test

  1. 1) ACTIVE DTC 

    Crank the engine.

    Ignition on, engine not running.

    With a scan tool, select View DTCs.

    Is the DTC Active at this time? 

    Yes 

    1. Go to  2).

    No 

    1. Go to  14).
  2. 2) (F856) 5-VOLT SUPPLY CIRCUIT 
    Fig 1: Measuring Voltage On (F856) 5-Volt Supply Circuit In CMP Sensor Harness Connector
    GC0064203Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the CMP Sensor harness connector.

    Ignition on, engine not running.

    Measure the voltage on the (F856) 5-volt Supply circuit in the CMP Sensor harness connector.

    Is the voltage between 4.5 and 5.2 volts? 

    Yes 

    1. Go to  3).

    No 

    1. Go to  10).
  3. 3) (K44) CMP SIGNAL CIRCUIT 
    Fig 2: Measuring Voltage On (K44) CMP Signal Circuit In CMP Sensor Harness Connector
    GC0064204Courtesy of CHRYSLER LLC

    Measure the voltage on the (K44) CMP Signal circuit in the CMP Sensor harness connector.

    Is the voltage between 4.5 and 5.0 volts? 

    Yes 

    1. Go to  4).

    No 

    1. Go to  7).
  4. 4) (K900) SENSOR GROUND CIRCUIT OPEN 
    Fig 3: Measuring Resistance Of (K900) Sensor Ground Circuit From CMP Sensor Harness Connector To Appropriate Terminal Of Special Tool #8815
    GC0064205Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C1 and C2 PCM harness connectors.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (K900) Sensor ground circuit from the CMP Sensor harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  5).

    No 

    1. Repair the open in the (K900) Sensor ground circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  5. 5) (K44) CMP SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT 
    Fig 4: Measuring Resistance Between (K44) CMP Signal Circuit And (F856) 5-Volt Supply Circuit In CMP Sensor Harness Connector
    GC0064206Courtesy of CHRYSLER LLC

    Measure the resistance between the (K44) CMP Signal circuit and the (F856) 5-volt Supply circuit in the CMP Sensor harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short between the (K44) CMP Signal circuit and the (F856) 5-volt Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  6).
  6. 6) CAMSHAFT POSITION SENSOR 
    NOTE: Inspect the Camshaft sprocket for damage per the Service Information. If a problem is found repair as necessary.

    If there are no possible causes remaining, view repair. 

    Repair 

    1. Verify that there is good pin to terminal contact in the CMP Sensor and the Powertrain Control Module connectors. If OK, replace the Camshaft Position Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .
  7. 7) (K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 5: Measuring Voltage On (K44) CMP Signal Circuit In CMP Sensor Harness Connector
    GC0064204Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C2 PCM harness connector.

    Ignition on, engine not running.

    Measure the voltage on the (K44) CMP Signal circuit in the CMP Sensor harness connector.

    Is there any voltage present? 

    Yes 

    1. Repair the short to voltage in the (K44) CMP Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  8).
  8. 8) (K44) CMP SIGNAL CIRCUIT OPEN 
    Fig 6: Measuring Resistance Of (K44) CMP Signal Circuit From CMP Sensor Harness Connector To Appropriate Terminal Of Special Tool #8815
    GC0064207Courtesy of CHRYSLER LLC

    Turn the ignition off.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (K44) CMP Signal circuit from the CMP Sensor harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  9).

    No 

    1. Repair the open in the (K44) CMP Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  9. 9) (K44) CMP SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 7: Measuring Resistance Between Ground And (K44) CMP Signal Circuit In CMP Sensor Harness Connector
    GC0064208Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (K44) CMP Signal circuit in the CMP Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (K44) CMP Signal circuit
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  10).
  10. 10) (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE 
    Fig 8: Measuring Voltage On (F856) 5-Volt Supply Circuit In CMP Sensor Harness Connector
    GC0064203Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C1 PCM harness connector.

    Ignition on, engine not running.

    Measure the voltage on the (F856) 5-volt Supply circuit in the CMP Sensor harness connector.

    Is there any voltage present? 

    Yes 

    1. Repair the short to voltage in the (F856) 5-volt Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  11).
  11. 11) (F856) 5-VOLT SUPPLY CIRCUIT OPEN 
    Fig 9: Measuring Resistance Of (F856) 5-Volt Supply Circuit Between CMP Sensor Harness Connector To Appropriate Terminal Of Special Tool #8815
    GC0064209Courtesy of CHRYSLER LLC

    Turn the ignition off.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (F856) 5-volt Supply circuit between the CMP Sensor harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  12).

    No 

    1. Repair the open in the (F856) 5-volt Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  12. 12) (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND 
    Fig 10: Measuring Resistance Between Ground And (F856) 5-Volt Supply Circuit In CMP Sensor Harness Connector
    GC0064210Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (F856) 5-volt Supply circuit in the CMP Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (F856) 5-volt Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  13).
  13. 13) POWERTRAIN CONTROL MODULE (PCM) 

    Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Camshaft Position Sensor and the Powertrain Control Module (PCM).

    Look for any chafed, pierced, pinched, or partially broken wires.

    Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the CMP Sensor and the Powertrain Control Module connectors.

    Refer to any Technical Service Bulletins that may apply.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
  14. 14) ERRATIC CMP SIGNAL 

    With a lab scope probe and the Miller special tool #6801, back probe the (K44) CMP Signal circuit in the CMP harness connector.

    WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

    Ignition on, engine not running.

    Wiggle the related wire harness and lightly tap the Camshaft Position Sensor.

    Observe the lab scope screen.

    Allow the engine to idle.

    Observe the lab scope screen.

    Did the CMP Sensor generate any erratic pulses? 

    Yes 

    1. Verify that there is good pin to terminal contact in the CMP Sensor and the Powertrain Control Module connectors. If OK, replace the Camshaft Position Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  15).
  15. 15) ERRATIC CKP SIGNAL 

    Turn the ignition off.

    With a lab scope probe and the Miller special tool #6801, backprobe the (K24) CKP Signal circuit in the CKP harness connector.

    WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

    Ignition on, engine not running.

    Wiggle the related wire harness and lightly tap on the Crankshaft Position Sensor.

    Observe the lab scope screen.

    Allow the engine to idle.

    Observe the lab scope screen.

    Did the CKP Sensor generate any erratic pulses? 

    Yes 

    1. Verify that there is good pin to terminal contact in the CKP Sensor and the Powertrain Control Module connectors. If OK, replace the Crankshaft Position Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Test complete, the conditions that set this DTC are not present at this time
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