Diagnostic Test

WARNING: This page is about a different car, the 2016 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE CONDITION
1. Turn the ignition on.
2. With the scan tool, read DTCs. Record DTC and Freeze Frame information on the repair order.
3. With the scan tool, erase DTCs.
4. Operate the vehicle under the conditions which originally set this DTC or use the When Monitored and Set Conditions.
5. With the scan tool, view the Misfire Monitor to see which cylinders are effected.
  Are misfires being logged for a particular cylinder or is the DTC pending at this time?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
- Perform the applicable fuel, ignition component, or circuit diagnostic procedure(s). Refer to 3.6L - DIAGNOSTIC CODE INDEX - 1500 .
- Go to 3
PERFORM A GENERAL VISUAL INSPECTION OF ENGINE AND BELT DRIVEN ACCESSORIES
NOTE:
Anything that affects the speed of the crankshaft can cause a misfire DTC.

NOTE:
When a Misfire is detected for a particular cylinder, the PCM will shut down that cylinder's Injector Control circuit.
1. Visually inspect the engine for any of the following conditions:
  - Worn serpentine belt. Refer to BELT, SERPENTINE, DIAGNOSIS AND TESTING .
  - Binding Engine-Driven accessories: A/C Compressor, P/S Pump, Water pump.
  - Misalignment of the Water pump, P/S Pump and A/C Compressor pulleys.
  - Corroded PCM power and ground circuits.
  - Improper CKP, CMP, MAP and TPS mounting.
  - Poor connector/terminal to component connection for CKP Sensor, CMP Sensor, MAP Sensor, TPS, Fuel Injector, Ignition Coil, etc.
  - Vacuum leaks.
  - Restricted Exhaust system. Perform the CHECKING EXHAUST RESTRICTION diagnostic procedure. Refer to DIAGNOSIS AND TESTING .
  - Restricted Air Induction system.
  - Overfilled engine oil or transmission.
  - Extremely out of balance tires or warped brake rotors.
  Were any of the above conditions present?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK FOR A FUEL OR IGNITION SYSTEM PROBLEM
1. Start the engine and allow it to idle long enough for the O2 Sensor to warm up and go into closed loop operation. This may take a couple of minutes.
2. With the scan tool, observe the voltage reading of the Downstream O2 Sensor for the bank on which the misfire was present.
  NOTE:
  If the misfire is caused by a lack of fuel condition, the O2 Sensor voltage will tend to stay at the low end of the range (approximately 2.5 volts). If the misfire is caused by a lack of or poor quality spark condition, the O2 Sensor voltage will tend to stay at the high end of the voltage range (approximately 3.5 volts).
  
  Does the Downstream O2 Sensor voltage reading tend to be staying at the low end (2.5 volts) or high end (3.5 volts) of the voltage range.
  
  High end of the range (3.5 volts)
  - Go To 5
  Low end of the range (2.5 volts)
  - Go To 8
CHECK THE IGNITION SYSTEM FOR PROPER OPERATION
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.
1. Turn the ignition off.
2. Remove the Ignition Coils. Refer to COIL, IGNITION, REMOVAL .
3. Connect the Ignition Coil harness connectors.
4. Disconnect the Fuel Injector harness connector of the cylinder being tested.
5. Install a spark tester on the Ignition Coil.
6. While cranking the engine observe the spark coming from the spark tester.
  NOTE:
  Check all of the cylinders that were showing a misfire.
  
  NOTE:
  A crisp blue spark that is able to jump the gap of the spark tester should be generated at the coil on plug and at the end of the ignition wire.
  
  Is good spark present on all cylinders?
  
  Yes
  - Go To 6
  No
  - Go To 12
INSPECT THE SPARK PLUG
1. Turn the ignition off.
2. Remove the Spark Plug(s) in accordance with the Service Information. Refer to SPARK PLUG, REMOVAL .
3. Inspect the Spark Plug(s) for the following conditions:
  - Cracks
  - Carbon Tracking
  - Foreign Material
  - Gap size out of specifications
  - Loose or broken electrode
  NOTE:
  Lightly tap the bottom of the spark plug on a solid surface. The electrode in the spark plug should not move.
  
  Were any of the above conditions present?
  
  Yes
  - Replace the bad Spark Plug(s) in accordance with the service information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 7
EXCHANGE THE SPARK PLUG WITH A KNOWN GOOD CYLINDER
1. Exchange the Spark Plug with a known good cylinder that was not indicating a misfire.
2. Start the engine and monitor the misfire monitor screen.
  Did the misfire switch to the previously good cylinder?
  
  Yes
  - Replace the Spark Plug in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 11
CHECK THE FUEL DELIVERY SYSTEM
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
  NOTE:
  Fuel pressure specification is 400 kPa +/- 14 kPa (58 psi +/- 2 psi).
  
  Were any problems found with the fuel delivery system?
  
  Yes
  - Repair the Fuel Delivery system as necessary
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 9
CHECK THE FUEL INJECTOR CONTROL CIRCUIT WITH A NOID LIGHT
1. Turn the ignition off.
2. Disconnect the Fuel Injector harness connector of the misfiring cylinder.
3. Turn the ignition on.
  NOTE:
  When a Misfire is detected for a particular cylinder, the PCM will shut down that cylinder's Injector Control circuit.
4. Install an Injector Noid light.
5. With the scan tool, actuate the Fuel Injector.
  Does the Noid light blink/flicker during the actuation?
  
  Yes
  - Verify that there is good pin to terminal contact in the related Injector and the Powertrain Control Module connectors. Replace the Fuel Injector. Refer to INJECTOR(S), FUEL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 10
CHECK THE FUEL INJECTOR CONTROL CIRCUIT FOR AN OPEN OR SHORTED CONDITION
1. Turn the ignition off.
2. Remove the Injector Noid light.
3. Disconnect the PCM C2 harness connector.
4. Check the Injector Control circuit for an open, short to ground and short to voltage.
  Was a problem found with the Injector Control circuit?
  
  Yes
  - Repair the excessive resistance or short in the Injector Control circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 16
CHECK THE ENGINE MECHANICAL AND INTERNAL OPERATION
1. Check for any of the following conditions/mechanical problems:
  - ENGINE VACUUM - must be at least 13 inches in neutral
  - ENGINE VALVE TIMING - must be within specifications
  - ENGINE COMPRESSION - must be within specifications
  - CYLINDER LEAKAGE TEST - 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
  - VALVE SPRINGS - cannot be weak or broken
  - CAM LOBES - must not be worn excessively
  - CAM SHAFTS - must not be worn or have excessive endplay
  Are there any engine mechanical problems?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 16
CHECK THE ASD RELAY OUTPUT CIRCUIT
1. Connect the Fuel Injector harness connector before continuing.
2. Turn the ignition off.
3. Disconnect the Coil on Plug harness connector that did not produce a spark.
4. Turn the ignition on.
5. With a scan tool, actuate the ASD Relay.
6. Using a 12-volt test light connected to ground, probe the ASD Relay Output circuit in the Coil on Plug harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 13
  No
  - Repair the open or short to ground in the ASD Relay Output circuit between the PDC and Coil on Plug harness connector.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE IGNITION COIL CONTROL CIRCUIT
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.
1. Using a 12-volt test light connected to a 12 volt source, probe the Coil Control circuit at the Coil on Plug harness connector.
2. Crank the engine for 5.0 seconds while observing the test light.
  What is the condition of the test light while cranking the engine?
  
  Brightly blinking.
  - Replace the Ignition Coil in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  ON constantly.
  - Go To 14
  OFF constantly.
  - Go To 15
CHECK THE COIL CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Check for continuity between ground and the Coil Control circuit in the Coil on Plug harness connector.
  Is there continuity between ground and the Coil Control circuit?
  
  Yes
  - Repair the Coil Control circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 16
CHECK THE COIL CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the Coil Control circuit between the Coil on Plug harness connector and the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 16
  No
  - Repair the Coil Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED HARNESS 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. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect 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 in accordance with the Service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - 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 .
  - Test complete.