Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

CHECK FOR AN ACTIVE DTC
NOTE:
After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.
1. Start the engine.
2. Test drive the vehicle. Try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data, or in accordance with the When Monitored condition.
3. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE O2 SENSOR VOLTAGE READINGS
NOTE:
This DTC will set due to poor engine performance as well as a faulty O2 Sensor or wiring. If the vehicle exhibits any fuel system or driveability issues, or has any other driveability DTCs present, repair those concerns before proceeding with this test.
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/1 harness connector.
3. Connect the diagnostic adapter (special tool #10367, Adapter, Wideband O2 Sensor Diagnostic) in-line of the O2 Sensor 1/1 harness connector.
4. Start the engine and bring the engine speed up to 2500 RPM.
  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 may result in possible serious or fatal injury.
5. With the engine steady at 2500 RPM, measure the voltage:
  - at the (K41) O2 Sensor Signal circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
  - at the (K902) O2 Sensor Return circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
  - at the (K89) O2 Sensor Pump Current circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
  - between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit at the appropriate terminals of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
  NOTE:
  If the Powertrain Control Module detects an active open or short on any of the O2 Sensor 1/1 circuits, it will power down all of the O2 Sensor circuits to protect the O2 Sensor and PCM internal ASIC from being damaged.
6. If the O2 Sensor is powered up by the PCM and operating normal, the voltage readings should be as follows;
  - The voltage at the (K41) O2 Sensor Signal circuit should be approximately 4.3 volts.
  - The voltage at the (K902) O2 Sensor Return circuit should be approximately 3.85 volts.
  - The voltage at the (K89) O2 Sensor Pump Current circuit should be switching between approximately 3.4 volts and 4.3 volts.
  - The voltage between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit should switch between +0.45 volts and -0.45 volts.
  NOTE:
  The voltage readings may vary up or down slightly depending on the age of the O2 Sensor and operating conditions of the engine. However, if the engine and O2 Sensor are operating normal the voltage reading between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit should switch between +0.45 volts and -0.45 volts with very little or no change.
  
  Do the circuit voltages read as described?
  
  Yes
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
  No, voltage readings are at or near 0.0 volts
  - Go To 3
  No, voltage reading between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit is not switching between +0.45 volts and -0.45 volts
  - Go To 7
CHECK THE (F344) FUSED ASD RELAY OUTPUT VOLTAGE
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/1 harness connector.
3. Remove the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool. Leave the O2 Sensor 1/1 harness connector disconnected.
4. Turn the ignition on.
5. Measure the voltage on the (F344) Fused ASD Relay Output circuit at the O2 Sensor 1/1 harness connector.
  Is the voltage reading equal battery voltage?
  
  Yes
  - Go To 4
  No
  - Repair the (F344) Fused ASD Relay Output circuit for an open or short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE O2 SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
1. Measure for voltage at the:
  - (K41) O2 Sensor 1/1 Signal circuit at the O2 Sensor 1/1 harness connector.
  - (K902) O2 Sensor 1/1 Return circuit at the O2 Sensor 1/1 harness connector.
  - (K89) O2 Sensor 1/1 Positive Current Control circuit at the O2 Sensor 1/1 harness connector.
  NOTE:
  With the O2 Sensor disconnected, the PCM will power down the O2 Sensor and there should be no voltage on the circuits.
  
  Do any of the circuits measure above 0.5 volts?
  
  Yes
  - Repair the circuit that measured above 0.5 volts for a short to voltage.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE O2 SENSOR CIRCUITS FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Check for continuity between ground and the following circuits:
  - (K41) O2 Sensor 1/1 Signal circuit at the O2 Sensor 1/1 harness connector.
  - (K902) O2 Sensor 1/1 Return circuit at the O2 Sensor 1/1 harness connector.
  - (K89) O2 Sensor 1/1 Current Pump Control circuit at the O2 Sensor 1/1 harness connector.
  - (K79) O2 Sensor 1/1 Heater Control circuit at the O2 Sensor 1/1 harness connector.
  Is there continuity between any of the above circuits and ground?
  
  Yes
  - Repair any circuit(s) that showed continuity for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK THE O2 SENSOR CIRCUITS FOR AN OPEN OR HIGH RESISTANCE
1. Measure the resistance of the:
  - (K41) O2 Sensor 1/1 Signal circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
  - (K902) O2 Sensor 1/1 Return circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
  - (K89) O2 Sensor 1/1 Current Pump Control circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
  - (K79) O2 Sensor 1/1 Heater Control circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
  Is the resistance below 3.0 Ohms for each of the above circuits?
  
  Yes
  - Go To 13
  No
  - Repair the circuit that measured above 3.0 Ohms for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE O2 SENSOR PUMPING CURRENT
1. With the scan tool, navigate to data display and monitor or graph the O2 Sensor pump reading with the engine at 2500 RPM.
  NOTE:
  The O2 pump current should cycle between +0.12 mA and -0.12 mA if there are no fuel or ignition system issues.
  
  Follow the appropriate result below:
  
  The current is cycling more positive in relation to zero indicating a lean condition
  - Go To 8
  The current is cycling more negative in relation to zero indicating a rich condition
  - Go To 10
CHECKING THE INTAKE SYSTEM
1. Perform a check of the intake system for leaks or restrictions.
  Were any problems found?
  
  Yes
  - Perform the appropriate repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 9
CHECKING THE EXHAUST SYSTEM FOR LEAKS
1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .
  Were any exhaust leaks found?
  
  Yes
  - Repair or replace the leaking exhaust parts as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 10
CHECK THE FUEL DELIVERY SYSTEM
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
  Were any fuel system issues found?
  
  Yes
  - Perform the appropriate repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 11
MAP SENSOR OPERATION
1. Turn the ignition off.
2. Connect a Vacuum Gauge to a Manifold Vacuum source.
3. Start the engine.
4. Allow the engine to idle.
  NOTE:
  If engine will not idle, maintain a constant RPM above idle.
5. With the scan tool, read the MAP Sensor vacuum value.
  Is the scan tool reading within 1" of Hg on the Vacuum Gauge reading?
  
  Yes
  - Go To 12
  No
  - Verify that there is good pin to terminal contact in the MAP Sensor and Powertrain Control Module connectors. If OK, replace the MAP Sensor. Refer to SENSOR, MANIFOLD AIR PRESSURE (MAP), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
ENGINE MECHANICAL PROBLEM
1. Turn the ignition off.
2. Check for any of the following conditions/mechanical problems:
  - AIR INDUCTION SYSTEM - must be free from leaks.
  - ENGINE VACUUM - must be at least 13 inches in neutral
  - ENGINE VALVE TIMING - must be within specifications
  - ENGINE COMPRESSION - must be within specifications
  - ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
  - ENGINE PCV SYSTEM - must flow freely
  - TORQUE CONVERTER STALL SPEED - must be within specifications
  - POWER BRAKE BOOSTER - no internal vacuum leaks
  - FUEL - must be free of contamination
  - FUEL INJECTOR - plugged or restricted injector; control wire not connected to correct injector
  Are there any engine mechanical problems?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 13
O2 SENSOR
1. Replace the Oxygen Sensor in accordance with the service information and reconnect the harness connector. Refer to SENSOR, OXYGEN, REMOVAL .
2. Turn the ignition on, start the engine.
3. Allow the engine to reach normal operating temperature.
4. Test drive the vehicle in the conditions in which the fault originally set by reviewing the Freeze Frame data, or by following the when monitored conditions.
5. With the scan tool, read DTCs.
  NOTE:
  It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
  
  Is the DTC active or pending?
  
  Yes
  - Go To 14
  No
  - Repair complete.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all PCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. 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.
6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Powertrain Control Module in accordance with the service information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  - Test complete.