Diagnostic Instructions
DTC Descriptor
DTC P042E: Exhaust Gas Recirculation (EGR) Closed Position Performance
Circuit/System Description
The exhaust gas recirculation (EGR) valve is driven by the EGR motor, and the EGR motor is controlled by the engine control module (ECM). The EGR position sensor generates a signal according to the position of the EGR motor. The EGR valve has the following
circuits:
| • | The EGR motor U position drive circuit |
| • | The EGR motor V position drive circuit |
| • | The EGR motor W position drive circuit |
| • | A 5-volt reference circuit |
| • | A low reference circuit |
| • | The EGR motor U position signal circuit |
| • | The EGR motor V position signal circuit |
| • | The EGR motor W position signal circuit |
The ECM supplies voltage to the EGR motor on the EGR motor drive circuits. The EGR valve is controlled by the time of voltage supply from the ECM to the EGR motor. When the time of voltage supply increases, the EGR valve position decreases. The ECM detects
the actual EGR valve operation with the mass air flow (MAF) ratio.
Conditions for Running the DTC
| • | DTCs P0112, P0113, P0117, P0118, P0126, P0403, P0404, P0409, P0652, P0653, P2227, P2228, and P2229 are not set. |
| • | The battery voltage is between 10-16 volts. |
| • | The ignition switch is ON for longer than 2 seconds. |
| • | The engine coolant temperature is between 55-100°C (131-212°F). |
| • | The intake air temperature is between -7 and +150°C (+19 and +302°F). |
| • | The barometric pressure is between 80-120 kPa. |
| • | The absolute value of target EGR change position is less than 0 percent for more than 1 second. |
Conditions for Setting the DTC
| • | The ECM detects that the EGR learned minimum position is more than 23 percent, and the actual EGR valve position is more than 5 percent for 3 seconds. |
| • | The ECM detects that the EGR learned minimum position is less than 7 percent, and the actual EGR valve position is more than 5 percent for 3 seconds. |
Action Taken When the DTC Sets
DTC P042E is a Type B DTC.
Conditions for Clearing the DTC
DTC P042E is a Type B DTC.
Diagnostic Aids
Inspect for any recent engine mechanical repairs. An incorrectly installed EGR sensor will cause this DTC to set.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
Verify the integrity of the EGR sensor by inspecting for the following conditions:
| • | Loose or improper installation |
Circuit/System Testing
Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
- Ignition ON and the EGR valve harness disconnected, measure for 0 volts on the EGR valve position drive circuits.
| ⇒ | If the voltage is more than 0 volts, test the affected motor control circuit for a short to voltage. If the circuits test normal, replace the ECM. |
- Ignition ON and the EGR valve harness disconnected, probe the EGR valve position drive circuits with a test lamp connected to battery voltage. Verify the test lamp does not illuminate on either circuit.
| ⇒ | If the test lamp illuminates, test the affected motor control circuit for a short to ground. If the circuits test normal, replace the ECM. |
- Ignition ON and the EGR valve connected, clear all DTCs.
- Ignition OFF, allow sufficient time for the control module to power down before disconnecting the EGR valve connector.
- Using the peak Min Max function, measure the voltage on the valve position drive circuits as the ignition is turned ON. Voltage should be within 1 volt of the ignition voltage.
| ⇒ | If voltage is less than the specified range, test the valve position drive circuits circuit for high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If all circuits test normal, replace the EGR valve. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
