EGR Flow Sensor A Low Circuit Input..PO405

[claytonr]

ok so this dam code keeps coming up... its obvious that the wire might be pinched of severed which would cause the low input. or the sensor itself is damaged. any ideas or has this code ever popped up with yal..

EGR Flow Sensor A Low Circuit Input..PO405

[Phantom2kz]

.


The PCM monitors the position of the EGR valve through a feedback signal. The PCM supplies a 5.0 volt reference and a ground to the EGR valve. A voltage signal representing the EGR valve pintle position is sent to the PCM from the EGR valve. This feedback signal can also be monitored on a scan tool and is the actual position of the EGR pintle. The Actual EGR Position should always be near the commanded or Desired EGR Position.

Conditions for Running the DTC
The ignition voltage is more than 11.7 volts.

Conditions for Setting the DTC
• The EGR feedback signal voltage is less than 0.14 volts.

• All conditions are present for 10 seconds.

Action Taken When the DTC Sets
• The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

• The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
• The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.

• A last test failed, or current DTC, clears when the diagnostic runs and does not fail.

• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

• Use a scan tool in order to clear the MIL and the DTC.

Diagnostic Aids
Important:

• Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM.

• For any test that requires probing the PCM or a component harness connector, use the J 35616 connector test adapter kit. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.


Due to the moisture associated with exhaust systems, the EGR valve may freeze and stick in colder weather at times. After the vehicle is brought into a warm shop for repairs, the valve warms and the concern disappears. By monitoring the Actual EGR and Desired EGR Positions on a cold engine with a scan tool, the fault can be verified easily.

For an intermittent, refer to Symptoms .

Test Description
The numbers below refer to the step numbers on the diagnostic table.

If DTC P1635 sets at the same time, this indicates that the 5 voltage reference circuit is either shorted to a ground or shorted to a voltage. The 5 volt reference circuit is internally connected within the PCM. The MAP sensor circuits may be causing this DTC to set. Refer to DTC P1635 for further diagnosis.

This step determines if the malfunction is present.

Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This isolates when the DTC failed.

If the scan tool displays 5 volts, the EGR pintle position signal, 5 volt reference circuit, and the PCM are OK.

If the scan tool displays 5 volts, the EGR pintle position signal circuit and the PCM are OK.

Disconnecting the PCM allows using the DMM in order to test the continuity of the circuits. This aids in locating an open or a shorted circuit.

Step
Action
Value(s)
Yes
No

1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check

2
Install a scan tool.
Idle the engine.
Monitor the Diagnostic Trouble Code (DTC) Information using the scan tool.
Did DTC P1635 fail this ignition cycle?
--
Go to DTC P1635 5 Volt Reference 1 Circuit
Go to Step 3

3
Monitor the EGR pintle position voltage on Engine 1 Data List on the scan tool.

Is the EGR pintle position voltage below the specified value?
0.14V
Go to Step 5
Go to Step 4

4
Turn ON the ignition leaving the engine OFF.
Review the Freeze Frame and/or Failure Records data for this DTC and observe the parameters.
Turn OFF the ignition for 15 seconds.
Start the engine.
Operate the vehicle within the conditions required for this diagnostic to run, and as close to the conditions recorded in the Freeze Frame/Failure Records as possible. Special operating conditions that you need to meet before the PCM will run this diagnostic, where applicable, are listed in Conditions for Running the DTC.
Select the Diagnostic Trouble Code (DTC) option, the Specific DTC option, then enter the DTC number using the scan tool.
Does the scan tool indicate that this diagnostic failed this ignition?
--
Go to Step 5
Go to Diagnostic Aids

5
Disconnect the EGR valve electrical connector.
Jumper the 5 volt reference circuit and the EGR pintle signal circuit together at the EGR valve harness connector.
Observe the EGR pintle position voltage display on the scan tool.
Is the EGR pintle position voltage near the specified value?
5 Volts
Go to Step 11
Go to Step 6

6
Connect the test lamp J 35616-200 between B+ and the EGR pintle position signal circuit at the EGR valve harness connector.
Observe the EGR pintle position voltage display on the scan tool.
Is the voltage near the specified value?
5 Volts
Go to Step 7
Go to Step 9

7
Turn OFF the ignition.
Disconnect the PCM connector C1 located on the same side as the manufacturer's logo. Refer to Powertrain Control Module Replacement/Programming .
Test the 5 volt reference circuit for the following:
• an open

• a short to a ground

• a short to a voltage

If you find the 5 volt reference circuit is open or shorted, repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 8

8
Inspect the 5 volt reference circuit for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If you find a poor connection repair the terminal as necessary. Refer to Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 13

9
Turn OFF the ignition.
Disconnect the PCM connector C1 located on the same side as the manufacturer's logo. Refer to Powertrain Control Module Replacement/Programming .
Test the EGR pintle position signal circuit for the following:
• Open circuit

• Short to a ground

• Short to sensor ground circuit

If you find the EGR pintle position signal circuit is open or shorted to a ground, repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 10

10
Inspect the EGR pintle position signal circuit for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If you find a poor connection repair the terminal as necessary. Refer to Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 13

11
Inspect for poor connections at the EGR valve. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If you find a poor connection, repair the terminal as necessary. Refer to Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 12

12
Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement .

Is the action complete?
--
Go to Step 14
--

13
Important:: Program the replacement PCM. Refer to Powertrain Control Module Replacement/Programming .

Replace the PCM.

Is the action complete?
--
Go to Step 14
--

14
Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.
Idle the engine at the normal operating temperature.
Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.
Does the scan tool indicate that this test ran and passed?
--
Go to Step 15
Go to Step 2

15
Select the Capture Info option and the Review Info option using the scan tool.

Does the scan tool display any DTCs that you have not diagnosed?

[claytonr]

dam that was alot of stuff that i dont know what it means any advice in english no offense or anything but that is very compicated sounding?!!!!

[2001NBMZ28]

Same info, little different format with a diagram if you want to troubleshoot it yourself: www.gearchatter.com/viewtopic8861.php Friend of mine just deleted the EGR on his car, we don't have emissions here in Florida though.