Diagnostic Test

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 10.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
Did the DTC return?

Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE ENGINE OIL/ENGINE MECHANICAL CONDITION
NOTE:
Make sure that the engine oil is at the proper level. Also, review the customers oil change history to ensure that the oil is being changed at the correct intervals and that the proper oil viscosity is being used.
1. The following items should be considered before determining the cause of this DTC. Failure to do so may lead to misdiagnosis.
  - ENGINE MECHANICAL TOLERANCES OUT OF SPECIFICATION
  - ENGINE OIL PRESSURE OUT OF SPECIFICATION
  - LOW ENGINE OIL
  - DETERIORATED OR DIRTY OIL
  - ENGINE OIL CONTAMINATED (i.e., coolant and/or fuel)
  NOTE:
  If any of the above conditions are found, repair as necessary.
  
  Were any of the above conditions present?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR PROPER VOLTAGE AT THE EOP SENSOR HARNESS CONNECTOR
1. Turn the ignition off.
2. Disconnect the harness connector at the component of the circuit being tested. Note: The ECU harness connector should still be connected during this test step.
3. Turn the ignition on.
4. Set the DVOM to measure DC voltage.
5. Connect the negative lead of the DVOM to a known good ground.
6. With the positive lead of the DVOM, measure the voltage of the circuit being tested at the component harness connector.
NOTE:
Normal operating voltage should be between 4.8 and 5.2 volts.

Does the circuit have the proper voltage present?

Yes
- Go To 4
No
- Repair the (F856) 5-Volt Supply circuit for an open or short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
ISOLATE AND CHECK THE EOP SENSOR (G6) PRESSURE SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note: Use the appropriate SYSTEM WIRING DIAGRAM as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note: The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
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 the GPEC Diagnostic Adaptor to perform the diagnosis.

NOTE:
IMPORTANT - The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.
1. If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
ISOLATE AND CHECK THE (K900) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note: Use the appropriate SYSTEM WIRING DIAGRAM as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note: The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
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 the GPEC Diagnostic Adaptor to perform the diagnosis.

NOTE:
IMPORTANT - The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.
1. If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE ABILITY OF THE PCM TO READ THE EOP SENSOR SIGNAL
1. Turn the ignition off.
2. Connect the PCM harness connector.
3. Connect a fused jumper between the (F856) 5-Volt Supply circuit and the (G6) Oil Pressure Signal circuit at the EOP Sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, read DTCs.
  NOTE:
  The P0523-ENGINE OIL PRESSURE SENSOR CIRCUIT HIGH DTC should set with the jumper in place.
6. Connect a jumper between the (K900) Sensor Ground circuit and the (G6) Oil Pressure Signal circuit.
  NOTE:
  The P0522-ENGINE OIL PRESSURE SENSOR CIRCUIT LOW DTC should set with the jumper in place.
7. With the scan tool, read DTCs.
  Does the scan tool display as described above?
  
  Yes
  - Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors. Remove the Engine Oil Pressure Sensor and ensure the oil passage/port is free from any blockage. If no problem is found, replace the Engine Oil Pressure Sensor. Refer to ENGINE SENSORS, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 7
    NOTE:
    Remove the jumper before continuing.
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .