Circuit Description
This diagnostic monitors the exhaust gas recirculation (EGR) valve for faults in the EGR valve electrical circuit. The powertrain control module (PCM) controls the EGR valve with a solid state device called a driver. The driver supplies the EGR solenoid with 12 volts that is pulse width modulated (PWM) through the EGR solenoid high control circuit. A ground path is provided by the PCM through the EGR solenoid low control circuit. The driver has the ability to detect an electrical malfunction on the EGR solenoid control circuits. If the PCM determines that the driver has detected an electrical malfunction on one of these circuits, this DTC sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0403 Exhaust Gas Recirculation (EGR) Solenoid Control Circuit
Conditions for Running the DTC
| • | DTC P0030, P0050, P0097, P0098, P0107, P0108, P0117, P0118, P0135, P0155, P0335, P0336, P0401, P0404, P0406, P0641, P0651, P1128, P1129, P2238, P2239, P2241, P2242, P2243, P2245, P2247, P2249, P2252, P2253, P2255, P2256, P2413, P2414, P2415, P2630, and P2631 are not set. |
| • | Battery voltage is at least 10.5 volts. |
| • | The engine is running. |
| • | The EGR is operating between 2-98 percent duty cycle. |
| • | DTC P0403 runs continuously once the above conditions have been met. |
Conditions for Setting the DTC
| • | The PCM detects an electrical malfunction in the EGR solenoid control circuit. |
| • | The above condition is present for more than 5 seconds. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step checks for an open in the EGR solenoid control circuit. The PCM provides a 12 volt bias signal on the solenoid control circuit that is pulled low when the solenoid is OK and has a good ground.
-
This step tests whether the PCM is actually commanding ON the EGR valve.
-
After replacing the PCM a new minimum throttle position and idle speed must be established.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Is the EGR Sensor parameter within the specified value? | 3.0-3.2 V | Go to Step 3 | Go to Step 4 |
3 |
Did the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions |
4 |
Is the solenoid resistance within the specified value? | 6.3-7.0 ohms at 20°C (68°F) | Go to Step 5 | Go to Step 11 |
Is the voltage near the specified value? | 12 V | Go to Step 6 | Go to Step 7 | |
Does the test lamp illuminate? | -- | Go to Step 9 | Go to Step 8 | |
7 | Test the EGR solenoid high control circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 |
8 | Test the EGR solenoid ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct a condition? | -- | Go to Step 13 | Go to Step 12 |
9 | Test for an intermittent and for a poor connection at the EGR valve. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 |
10 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 |
11 | Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- |
Did you complete the replacement? | -- | Go to Step 13 | -- | |
13 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 14 |
14 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
