P0405

Diagnostic Chart 1 Of 2:

Diagnostic Chart 2 Of 2:

Schematic:

CIRCUIT DESCRIPTION
The PCM monitors the EGR valve pintle position input to ensure that the valve responds properly to commands from the PCM and to detect a fault if the pintle position sensor circuit is open or shorted. If the PCM detects an excessively low EGR feedback signal voltage, DTC P0405 will set.

CONDITIONS FOR RUNNING THE DTC
The system voltage is more than 10 volts.

CONDITIONS FOR SETTING THE DTC
^ The EGR feedback is less than 0.14 volt at any time.
^ The condition is present for longer than 20 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test runs and fails.
^ The PCM disables EGR for the rest of the ignition cycle.
^ The PCM stores the conditions that were present when the DTC set as Freeze Frame and Fail Records data.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM turns the MIL OFF during the third consecutive trip in which the diagnostic runs and passes.
^ The history DTC clears after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

DIAGNOSTIC AIDS
^ A poor connection at the PCM or the EGR valve.
Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connections. Use a corresponding mating terminal to check for correct terminal tension.
^ A damaged harness.
Inspect the wiring harness for damage. If the harness appears to be OK, connect a digital multimeter (DMM) and check the circuit continuity while moving the connectors and the related wiring harnesses. A change in the DMM display will indicate the location of the malfunction.

TEST DESCRIPTION
Numbers below refer to the step numbers on the Diagnostic Table.
2. Verifies that the malfunction is present.
3. If DTC P0405 will only set under certain conditions, the malfunction may be intermittent; refer to Diagnostic Aids. If an intermittent wiring problem is not present, check for a poor connection at the PCM or the EGR valve
18. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.