:  Dec 17, 2007



Overview

For information on the operation of the emission control systems, refer to relevant workshop manual section.

Inspection and verification

. Verify the customer concern.

. Visually inspect for obvious mechanical or electrical faults.

Mechanical Electrical
  • Engine breather hoses
  • Oil separator
  • Exhaust gas recirculation (EGR) pipes (check for cracks)
  • EGR valve(s)
  • EGR cooler(s)
  • Fuse(s)
  • Wiring harness
  • Loose or corroded electrical connector(s)
  • Intake air shut off throttle
  • EGR valve(s)
  • Engine control module (ECM)

. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

. Use the approved diagnostic system or a scan tool to retrieve any diagnostic trouble codes (DTCs) before moving onto the symptom chart or DTC index.
  Make sure that all DTCs are cleared following rectification
Make sure that all DTCs are cleared following rectification

Symptom Chart

Symptom (specific) Possible cause Action
Difficult to start
  • EGR valve stuck open
Check the EGR valve.
Poor/Erratic idle
Lack of power when accelerating
Engine stops/stalls
  • EGR valve stuck open
  • Breather system disconnected/restricted/blocked
Check the EGR valve. Check the engine breather system. Check the oil separator. Check for EGR DTCs.
Excessive fuel consumption
  • EGR valve stuck open
  • EGR not operating
  • Breather system restricted/blocked
Excessive black smoke
Excessive emissions
Excessive blow-by
  • Breather system restricted/blocked
Check the engine breather hoses. Check the oil separator.
Engine oil leaks
  • Breather system restricted/blocked
Check the engine breather hoses. Check the oil separator.

DTC index

:
  Generic scan tools may not read the codes listed, or may read only 5-digit codes. Match the 5 digits from the scan tool to the first 5 digits of the 7-digit code listed to identify the fault (the last 2 digits give extra information read by the manufacturer-approved diagnostic system).

:
  For a more comprehensive symptom chart, refer to workshop manual section 303-14 - Electronic Engine Controls

DTC Description Possible cause Action
P040100 Exhaust Gas Recirculation A Flow Insufficient Detected
  • Exhaust gas recirculation (EGR) valve incorrectly installed or loose
  • EGR pipe blocked
  • EGR valve stuck closed, blocked
  • EGR coolers blocked
  • EGR valve failure
  • MAF sensor fault
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040200 Exhaust Gas Recirculation A Flow Excessive Detected
  • Exhaust gas recirculation (EGR) valve incorrectly installed or loose
  • EGR pipe blocked
  • EGR valve stuck/sticking
  • EGR coolers blocked
  • EGR valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
  • MAF sensor fault
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040300 Exhaust Gas Recirculation A Control Circuit
  • Exhaust gas recirculation (EGR) valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040400 Exhaust Gas Recirculation A Control Circuit Range/Performance
  • Intake air temperature (IAT) sensor fault
  • Manifold air pressure (MAP) sensor fault
  • MAF sensor fault
  • Exhaust gas recirculation (EGR) valve stuck/sticking
  • EGR valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040500 Exhaust Gas Recirculation Sensor A Circuit Low
  • Exhaust gas recirculation (EGR) valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve failure
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040600 Exhaust Gas Recirculation Sensor A Circuit High
  • Exhaust gas recirculation (EGR) valve circuit short circuit to power
  • EGR valve failure
Refer to the relevant workshop manual section. Check the EGR valve, coolers and pipework. Refer to the electrical guides and check the MAF sensor and circuits. Allow the engine to warm up, switch off and turn the ignition on. Using a data logger function, check the EGR valve angle. Command the valve actuator to 0% then 100% pulse width modulated (PWM) and recheck the values. The angle should range between 5% and 95%. If this is not the case, install a new valve as necessary. Clear the DTCs and test for normal operation.
P040700 Exhaust Gas Recirculation Sensor B Circuit Low
  • Exhaust gas recirculation (EGR) throttle position sensor circuit high resistance
  • EGR throttle position sensor circuit short circuit to ground
  • EGR modulator failure
Check the EGR throttle position sensor and circuits. Refer to the electrical guides. If no fault is found in the circuits, install a new EGR valve. Clear the DTCs and test for normal operation.
P040800 Exhaust Gas Recirculation Sensor B Circuit High
  • Exhaust gas recirculation (EGR) throttle position sensor circuit short circuit to power
  • EGR modulator failure
Check the EGR throttle position sensor and circuits. Refer to the electrical guides. If no fault is found in the circuits, install a new EGR valve. Clear the DTCs and test for normal operation.
P048700 Exhaust Gas Recirculation Throttle Control Circuit A / Open
  • Exhaust gas recirculation (EGR) throttle position sensor circuit high resistance
  • Exhaust gas recirculation (EGR) throttle position sensor circuit short circuit to ground
  • Exhaust gas recirculation (EGR) throttle position sensor circuit short circuit to power
  • EGR modulator failure
Check the EGR throttle position sensor and circuits. Refer to the electrical guides. Using a data logger function, check the EGR throttle position with the ignition on, engine off and record the value. Command the actuator to 100% pulse width modulated (PWM) and recheck the position reading. The value should be 80 - 95%. Command the actuator to 0% pulse width modulated (PWM) and recheck the position reading. The value should be 5 - 20%. Manually close and open the throttle and check the resistance. The resistance should range from 300 - 2,500 ohms. If the values are not in this range, install a new EGR valve. Clear the DTCs and test for normal operation. If there is still an issue, suspect the ECM. Refer to the warranty policy and procedures manual if an ECM is suspect.
P048800 Exhaust Gas Recirculation Throttle Control Circuit A Range/Performance
  • Exhaust gas recirculation (EGR) throttle position sensor circuit high resistance
  • Exhaust gas recirculation (EGR) throttle position sensor circuit short circuit to ground
  • Exhaust gas recirculation (EGR) throttle position sensor circuit short circuit to power
  • EGR modulator failure
Check the EGR throttle position sensor and circuits. Refer to the electrical guides. Using a data logger function, check the EGR throttle position with the ignition on, engine off and record the value. Command the actuator to 100% pulse width modulated (PWM) and recheck the position reading. The value should be 80 - 95%. Command the actuator to 0% pulse width modulated (PWM) and recheck the position reading. The value should be 5 - 20%. Manually close and open the throttle and check the resistance. The resistance should range from 300 - 2,500 ohms. If the values are not in this range, install a new EGR valve. Clear the DTCs and test for normal operation. If there is still an issue, suspect the ECM. Refer to the warranty policy and procedures manual if an ECM is suspect.
P133400 EGR Throttle Position Sensor Minimum/Maximum Stop Performance
  • Exhaust gas recirculation (EGR) valve stuck/sticking
  • EGR valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • Intake air shut off throttle stuck/sticking
  • Intake air shut off throttle circuit high resistance
  • Intake air shut off throttle circuit short circuit to ground
  • Intake air shut off throttle circuit short circuit to power
  • Intake air shut off throttle failure
  • ECM failure
Check the EGR valve and circuits. Refer to the electrical guides. Refer to the relevant workshop manual section. Refer to the warranty policy and procedures manual if a module is suspect.
P133500 EGR Position Sensor Minimum/Maximum Stop Performance
  • EGR valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Check the EGR valve and circuits. Refer to the electrical guides. Using a datalogger function, check the EGR valve angles and command the valve to 0% pulse width modulated (PWM). Recheck the angle. The value should be 0 - 20%. If the value is outside this range, install a new valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P140A00 Exhaust Gas Recirculation Sensor C Circuit Low
  • EGR valve circuit (left-hand bank) high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve failure
Check the EGR valve and circuits. Refer to the electrical guides. Using a datalogger function, check the EGR valve angle with the ignition on and the engine off. Command the valve angle to 0% pulse width modulated (PWM), then to 100% pulse width modulated (PWM) and recheck the angles. The angles should range between 0 - 20% and 80 - 95%. If this is not the case, install a new valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P140B00 Exhaust Gas Recirculation Sensor C Circuit High
  • EGR valve circuit (left-hand bank) short circuit to power
  • EGR valve failure
Check the EGR valve and circuits. Refer to the electrical guides. Using a datalogger function, check the EGR valve angle with the ignition on and the engine off. Command the valve angle to 0% pulse width modulated (PWM), then to 100% pulse width modulated (PWM) and recheck the angles. The angles should range between 0 - 20% and 80 - 95%. If this is not the case, install a new valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P140C00 Exhaust Gas Recirculation Control Circuit B
  • Intake air shut off throttle circuit high resistance
  • Intake air shut off throttle circuit short circuit to ground
  • Intake air shut off throttle circuit short circuit to power
  • Intake air shut off throttle failure
  • ECM failure
Check the EGR valve and circuits. Refer to the electrical guides. Refer to the warranty policy and procedures manual if a module is suspect.
P140D00 Exhaust Gas Recirculation Control Circuit B Range/Performance
  • Exhaust gas recirculation (EGR) control circuit range/performance (left-hand bank)
  • Intake air temperature (IAT) sensor fault
  • Manifold absolute pressure (MAP) sensor fault
  • Mass air flow (MAF) sensor fault
  • EGR valve stuck closed, blocked
  • EGR valve circuit high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Check the IAT, MAP and MAF sensors and circuits. Refer to the electrical guides. For left-hand bank EGR valve circuit tests, refer to the relevant workshop manual section.
P140E00 EGR Position Sensor C Minimum/Maximum Stop Performance
  • Exhaust gas recirculation (EGR) valve circuit (left-hand bank) high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Check the EGR valve and circuits. Refer to the electrical guides. Using a datalogger function, check the EGR valve angles and command the valve to 0% pulse width modulated (PWM). Recheck the angle. The value should be between 0 - 20%. If the value is outside this range, install a new valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P141A00 Exhaust Gas Recirculation Sensor A Circuit Intermittent/Erratic
  • EGR valve circuit (right-hand bank) high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
Check the EGR valve and circuits. Refer to the electrical guides. Start the engine and allow to warm up. Using a datalogger function, check the EGR valve position. After a further 5 seconds, recheck the position. If the value has increased by more than 80% per 10 ms, recheck the circuits. If no fault is found in the circuits, install a new EGR valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P141B00 Exhaust Gas Recirculation Sensor B Circuit Intermittent/Erratic
  • Intake air shut off throttle circuit high resistance
  • Intake air shut off throttle circuit short circuit to ground
  • Intake air shut off throttle circuit short circuit to power
  • Intake air shut off throttle failure
Check the EGR valve and circuits. Refer to the electrical guides. Start the engine and allow to warm up. Using a datalogger function, check the EGR valve position. After a further 5 seconds, recheck the position. If the value has increased by more than 80% per 10 ms, recheck the circuits. If no fault is found in the circuits, install a new EGR valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P141C00 Exhaust Gas Recirculation Sensor C Circuit Intermittent/Erratic
  • EGR valve circuit (left-hand bank) high resistance
  • EGR valve circuit short circuit to ground
  • EGR valve circuit short circuit to power
  • EGR valve failure
  • ECM failure
Check the EGR valve and circuits. Refer to the electrical guides. Start the engine and allow to warm up. Using a datalogger function, check the EGR valve position. After a further 5 seconds, recheck the position. If the value has increased by more than 80% per 10 ms, recheck the circuits. If no fault is found in the circuits, install a new EGR valve. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P214100 Exhaust Gas Recirculation Throttle Control Circuit A Low
  • EGR sensor circuits short circuit (to ground/power/other circuits
  • EGR sensor circuits high resistance
  • EGR sensor fault
Check the EGR sensor circuits. Refer to the electrical guides. Rectify as necessary. Clear the DTCs and test for normal operation. Using a datalogger function, read the difference between the EGR throttle set point and the actual throttle position, and the EGR throttle position. Check that the throttle is open and command the throttle closed. Check that the throttle position value increases to above 90%. Check the difference between set point and actual. This value should not exceed either maximum 5% or minimum -15%. Check that the EGR throttle is not sticking. Install a new right-hand valve as necessary. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.
P214200 Exhaust Gas Recirculation Throttle Control Circuit A High
  • EGR sensor circuits short circuit (to ground/power/other circuits
  • EGR sensor circuits high resistance
  • EGR sensor fault
Check the EGR sensor circuits. Refer to the electrical guides. Rectify as necessary. Clear the DTCs and test for normal operation. Using a datalogger function, read the difference between the EGR throttle set point and the actual throttle position, and the EGR throttle position. Check that the throttle is open and command the throttle closed. Check that the throttle position value increases to above 90%. Check the difference between set point and actual. This value should not exceed either maximum 5% or minimum -15%. Check that the EGR throttle is not sticking. Install a new left-hand valve as necessary. Refer to the relevant workshop manual section. Clear the DTCs and test for normal operation.