LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2023 >> Grand Cherokee Altitude, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 46 (2.0L - DTCS P052B To P0629) >> DTC Troubleshooting >> P054B Cold Start Exhaust Camshaft Position Timing Over-Retarded - Bank 1 Sensor 2 >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. CHECK FOR OTHER DTCS 
    NOTE:

    During a cold start, if the engine speed drops below a calibrated minimum idle speed threshold, the base engine control monitor in the PCM will put the Camshafts back to lock pin position. The Camshafts will stay at lock pin until the engine speed goes back above a calibrated threshold. During this period the Cold Start Monitor diagnostic sees the Camshafts at lock pin and outside of the calibrated threshold and fail. Therefore, anything that can cause a stumble or dip in idle speed at start up can cause this DTC to set. Another likely cause can be a lack of oil to the Camshaft Phaser at initial start up due to excessive tarnish or sludge in the oil passages, incorrect viscosity oil or oil filter, a tarnished Cam Phaser Oil Control Valve sticking in cold weather, or oil drained back out of the Phaser from an extended period without the engine being started.

    1. Turn the ignition on.
    2. With the scan tool, read DTCs and record on the repair order.

      Including this DTC, are there any DTCs related to the following:

      • Crank/Cam Misalignment
      • Camshaft Position Performance
      • Camshaft Position Actuator Circuit
      • Fuel System
      • Ignition System
      • Lubrication System

      Yes 

      No 

      • Go To  2
  2. CHECK THE ENGINE OIL LEVEL AND CONDITION 
    1. Turn the ignition off.
    2. The following items should be checked before continuing with this procedure. Failure to do so may lead to misdiagnosis.
      • LOW ENGINE OIL LEVEL
      • CONTAMINATED, DIRTY, AERATED OR DETERIORATED ENGINE OIL
      • INCORRECT ENGINE OIL FILTER (DOES NOT MEET OEM SPECIFICATIONS)
      • ENGINE OIL PRESSURE OUT OF SPECIFICATION
      • INCORRECT ENGINE OIL VISCOSITY

      Were any of the above conditions present?

      Yes 

      • Repair the engine oiling or mechanical condition (i.e. improper oil drain back, oil sludge, damaged oil pump, pick-up tube or seal, etc.). If the engine oil was not at the proper level, top off the engine oil to the proper specification. Start the engine and allow it to idle for 2 - 3 minutes. Turn the engine off, ignition on, and using the scan tool, erase the DTC. Start the engine and drive the vehicle to verify repair. If the DTC does not return, repair is complete.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
      • If the DTC returns, Go To  3

      No 

      • Go To  3
  3. CHECK THE ENGINE OIL PRESSURE AND ENGINE MECHANICAL CONDITION 
    1. Install the applicable adaptor to the oil filter cap and install an oil pressure gauge to the adaptor. If the adaptor is not available, monitor the oil pressure reading with the scan tool.
    2. Start the engine and allow it to idle.
    3. Monitor the engine oil pressure reading on the gauge or scan tool.
      NOTE:

      If the oil pressure is below 14 psi or oscillating excessively, it can cause a delay in Cam Phaser movement sufficient enough to set a slow response DTC.

      Is the oil pressure reading stable and above 14.0 psi?

      Yes 

      • Go To  4

      No 

      • Repair the engine oiling or mechanical condition (i.e. improper oil drain back, oil sludge, damaged oil pump, pick-up tube or seal, etc.).
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. VERIFY AN ACTIVE CONDITION BY CHECKING THE CAM PHASER POSITION 
    NOTE:

    If a Cam Phaser or Oil Control Valve is stuck, there may also be a Crankshaft/Camshaft Timing Misalignment and/or Multiple Cylinder Misfire DTC present.

    1. What to monitor for during the test step:
      • The phaser not coming back to lock pin at idle.  This his could indicate a faulty phaser or oil control valve that is permanently stuck off lock pin or a Camshaft Position Solenoid that is electrically stuck on.
      • The actual position lagging or moving slowly toward the desired position.  This could indicate a faulty phaser or tarnished oil control valve that is dragging.
      • The actual position lagging and then overshooting the desired position  This could indicate a faulty phaser, oil control valve or Camshaft Position Solenoid that is intermittently sticking or binding and then overshoot when the condition goes away.
    2. Start the engine and allow the engine to idle.
    3. With the scan tool, monitor and compare the Exhaust Cam 1 actual  position value with the Exhaust Cam 1 desired  position value. After comparing the two values at idle, check and compare the values at several different engine speeds during the following steps.
    4. While monitoring the Exhaust Cam 1 actual position and desired position values:
      • Raise the engine speed quickly and hold steady for up to 30 seconds.
      • Lower the engine speed and hold steady at a level above idle (off of lock pin) for up to 30 seconds.
    5. Repeat the above steps multiple times and allow the engine to come back to idle while monitoring the actual position value to verify that the phaser is returning to lock pin position.

      Is the difference between the actual value and the desired value readings more than 6.0 degrees at idle or is the actual value lagging behind or overshooting the desired value?

      Yes, the difference is greater than 6.0 degrees at idle: 

      • Go To  5

      Yes, the actual reading is lagging or overshooting when changing the engine speeds indicating a binding or sticking: 

      • Go To  6

      No 

      • This fault is occurring due to an intermittent condition. The problem could be due to an intermittent sticking or dragging condition of one of the timing components listed in the possible causes table. The issue could be temperature related (I.E. Incorrect or broken down oil affecting operation during a cold start, or a tolerance issue in a component that is affected after a cold start/heat soak or after the engine is warmed to operating temperature). The issue could also be occurring during certain specific driving conditions. It may be necessary to test drive the vehicle under different load conditions to duplicate the issue.
  5. DETERMINE IF THE CAM PHASER ISSUE IS ELECTRICAL OR MECHANICAL 
    1. While the engine is at idle, disconnect the Camshaft 1/2 Position Solenoid harness connector.
    2. The Exhaust Cam 1 actual position value should change to lock pin with the solenoid disconnected. The Exhaust Cam position should be at approximately 117.0 degrees at lock pin.

      Did the Exhaust Cam 1 actual value change to lock pin position with the solenoid unplugged?

      Yes 

      • Check the (K276) VVT Exhaust Control 1/2 circuit for a short to voltage. If the circuit is not shorted to voltage, replace the Powertrain Control Module in accordance with the service information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  6
  6. CHECK THE CAMSHAFT 1/2 OIL CONTROL VALVE OPERATION 
    1. Turn the ignition off.
    2. Remove the Camshaft 1/2 Position Solenoid.
    3. Inspect the spring loaded spool valve on the Oil Control Valve.
      NOTE:

      The spring loaded spool valve should be flush with the surface of the Oil Control Valve when at rest.

    4. Push and release the spring loaded spool valve against the return spring with a small punch.
      NOTE:

      The spring loaded spool valve should move freely without binding and return to the flush position if there are no problems with the Oil Control Valve.

      Was the spring loaded spool valve flush and able to move freely without dragging or sticking?

      Yes 

      • Go To  7

      No 

  7. CHECK THE CAMSHAFT 1/2 POSITION SOLENOID OPERATION 
    1. Turn the ignition off.
    2. With the solenoid still removed, reconnect the Camshaft 1/2 Position Solenoid harness connector.
    3. Turn the ignition on.
    4. With the scan tool, actuate the Camshaft 1/2 Position Solenoid on and off several times.

      Does the Camshaft 1/2 Position Solenoid move freely without binding or sticking during actuation?

      Yes 

      • Go To  8

      No 

      • Replace the Camshaft 1/2 Position Solenoid in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  8. VERIFY THAT THE CAMSHAFT 1/2 POSITION SOLENOID IS ABLE TO MOVE THE PHASER 
    1. Exchange the Camshaft 1/2 Position Solenoid with the Camshaft 2/2 Position Solenoid.
      NOTE:

      The Intake and Exhaust Solenoids should not be interchanged.

    2. Reconnect the solenoid harness connectors.
    3. Turn the ignition on.
    4. With the scan tool, erase DTCs in the PCM.
    5. Test drive the vehicle under the conditions in which the fault was set.
    6. With the scan tool, read DTCs.

      Did the DTC move with the solenoid or stay with the original Camshaft?

      Moved with the solenoid 

      • Replace the Camshaft 1/2 Position Solenoid in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      Stayed with the original camshaft 

      • Go To  9
  9. CHECK THE EXHAUST CAMSHAFT 1/2 TONE WHEEL 
    1. Turn the ignition off.
    2. Check the alignment of the CMP Sensor Tone Wheel in accordance with the service information.

      Is the CMP Sensor Tone Wheel aligned correctly?

      Yes 

      No 

scientia non olet · About LEMON Manuals