Diagnostic Test

DTC IS ACTIVE
NOTE: Diagnose and repair any EGR signal circuit high or low DTCs before continuing with this procedure.
1. Turn the ignition on.
2. With the scan tool, select View DTCs. Record the DTC and Freeze Frame information.
3. Start the engine and allow it to reach operating temperature.
  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 possible serious or fatal injury.
  
  WARNING: The normal operating temperature of the EGR system is very high. Never work around or attempt to service any part of the EGR system until it has cooled.
  
  NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set.
  
  NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.
4. With a scan tool, select View DTCs.
  Is the status Active for this DTC?
  
  Yes
  - Go to step 2
  No
  - Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(F856) 5-VOLT SUPPLY CIRCUIT HIGH RESISTANCE

Fig 1: Performing Voltage Drop Test To 5-Volt Supply Circuit
Courtesy of CHRYSLER LLC
1. 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 the PCM Pinout Box 8815 along with the Adapter 8815-1 to perform the diagnosis.
2. Using a voltmeter, perform a voltage drop test by backprobing the (F856) 5-volt Supply circuit at the Exhaust Gas Recirculation Valve harness connector and probing the appropriate terminal of the PCM Pinout Box 8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter.
  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 possible serious or fatal injury.
3. Start the engine.
  Is the voltage below 0.5 of a volt?
  
  Yes
  - Go to step 3
  No
  - Repair the (F856) 5-volt Supply circuit for high resistance.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K34) EGR SIGNAL CIRCUIT HIGH RESISTANCE

Fig 2: Performing Voltage Drop Test To EGR Signal Circuit
Courtesy of CHRYSLER LLC
1. 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 the PCM Pinout Box 8815 along with the Adapter 8815-1 to perform the diagnosis.
2. Using a voltmeter, perform a voltage drop test by backprobing the (K34) EGR Signal circuit at the Exhaust Gas Recirculation Valve harness connector and probing the appropriate terminal of the PCM Pinout Box 8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter.
  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 possible serious or fatal injury.
3. Start the engine.
  Is the voltage below 0.5 of a volt?
  
  Yes
  - Go to step 4
  No
  - Repair the (K34) EGR Signal circuit for high resistance.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K900) SENSOR GROUND CIRCUIT HIGH RESISTANCE

Fig 3: Performing Voltage Drop Test To Sensor Ground Circuit
Courtesy of CHRYSLER LLC
1. 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 the PCM Pinout Box 8815 along with the Adapter 8815-1 to perform the diagnosis.
2. Using a voltmeter, perform a voltage drop test by backprobing the (K900) Sensor Ground circuit at the Exhaust Gas Recirculation Valve harness connector and probing the appropriate terminal of the PCM Pinout Box 8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter.
  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 possible serious or fatal injury.
3. Start the engine.
  Is the voltage below 0.5 of a volt?
  
  Yes
  - Go to step 5
  No
  - Repair the (K900) Sensor Ground circuit for high resistance.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(Z904) GROUND CIRCUIT OPEN OR HIGH RESISTANCE

Fig 4: Using 12-Volt Test Light Connected To 12 Volts To Check Ground Circuit In Exhaust Gas Recirculation Valve Harness Connector
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the Exhaust Gas Recirculation Valve harness connector.
3. Using a 12-volt test light connected to the 12 volts, check the (Z904) Ground circuit in the Exhaust Gas Recirculation Valve harness connector.
  NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
  
  Is the test light illuminated and bright?
  
  Yes
  - Go to step 6
  No
  - Repair the (Z904) Ground circuit for an open circuit of high resistance.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K35) EGR CONTROL CIRCUIT HIGH RESISTANCE
1. Turn the ignition off.
2. Connect the Exhaust Gas Recirculation Valve connector.
  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 PCM Pinout Box 8815 along with the Adapter 8815-1 to perform the diagnosis.
3. Using a voltmeter, perform a voltage drop test by backprobing the (K35) EGR Control circuit at the Exhaust Gas Recirculation Valve harness connector and probing the appropriate terminal of the PCM Pinout Box 8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter.
4. Start the engine and allow it to reach operating temperature.
  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.
5. With the scan tool, perform the EGR System Test.
6. Select OPEN to open the EGR valve.
7. Monitor the circuit voltage on the voltmeter.
  Is the voltage below 0.5 of a volt when the valve was opened during the system test?
  
  Yes
  - Go to step 7
  No
  - Repair the (K35) EGR Control circuit for excessive resistance.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
EXHAUST GAS RECIRCULATION VALVE
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Exhaust Gas Recirculation Valve and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins (TSBs) that may apply.
  Were any problems found?
  
  Yes
  - Repair or replace the EGR system components as necessary.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Replace the Exhaust Gas Recirculation Valve.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .