P140A

DTC P140A

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P140A

-
Exhaust Gas Recirculation (EGR) Cooler Bypass Position Sensor Exceeded Learning Limit

Circuit/System Description

The offset of the EGR cooler bypass valve is checked after the offset learning has been completed in after-run/post drive. The difference between the maximum and minimum EGR cooler bypass valve offset values is calculated by the Engine Control Module (ECM). If the difference is above a calibrated threshold or the offset learned value is not within a calibrated range, a fault is recognized. While the offset learning is active, the EGR cooler bypass valve is checked for a jammed valve. If the valve is stuck during opening or closing for a calibrated time, a fault is reported. If either of these conditions occur, the DTC will be set.

Conditions for Running the DTC

* DTC P1414, P2494, or P2495 is not set.

* The ignition is OFF and the engine is in after-run/post drive.

* The EGR cooler bypass Valve offset learning procedure is active or complete for current drive cycle.

* The Engine Coolant Temperature (ECT) is between 5-123°C (41-253°F).

* Battery voltage is greater than 10 V.

* The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

* The ECM detects that the difference between the minimum and maximum EGR cooler bypass valve learned offset values is greater than 50 %.

OR

* The ECM detects that the offset learned value for the EGR cooler bypass valve is not within a calibrated range.

OR

* The ECM detects a jammed EGR cooler bypass valve during opening or closing the valve for greater than 5 s.

Action Taken When the DTC Sets

DTC P140A is a Type B DTC.

Conditions for Clearing the DTC

DTC P140A is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics (LGH or LML) [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTC P245A should not be set.

• If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

2. Ignition ON, observe the scan tool Des EGR Cooler Bypass Vlv Position and the EGR Cooler Bypass Vlv Position parameters. Command the EGR cooler bypass valve from 0-100 % with a scan tool. The parameters should respond and remain within 3 % throughout the commanded range.

3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Note:
Perform the Circuit System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, remove the Q47 EGR cooler bypass valve. Refer to Exhaust Gas Recirculation Cooler Bypass Valve Replacement Exhaust Gas Recirculation Cooler Bypass Valve Replacement.

2. Inspect the Q47 EGR cooler bypass valve for the following conditions:

* A sticking, binding, or frozen EGR cooler bypass valve

* Any coking, soot build up, debris or damage that can cause the EGR cooler bypass valve to stick partially open or closed

• If a condition is found, replace the Q47 EGR cooler bypass valve.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Exhaust Gas Recirculation Cooler Bypass Valve Replacement Exhaust Gas Recirculation Cooler Bypass Valve Replacement

* Control Module References Control Module References for ECM replacement, programming and setup