Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P0544 03: Exhaust Gas Temperature (EGT) Sensor 1 Circuit Voltage Below ThresholdDTC P0544 07: Exhaust Gas Temperature (EGT) Sensor 1 Circuit Voltage Above Threshold
DTC P0545: Exhaust Gas Temperature (EGT) Sensor 1 Circuit Low Voltage
DTC P0546: Exhaust Gas Temperature (EGT) Sensor 1 Circuit High Voltage
DTC P2031 03: Exhaust Gas Temperature (EGT) Sensor 2 Circuit Voltage Below Threshold
DTC P2031 07: Exhaust Gas Temperature (EGT) Sensor 2 Circuit Voltage Above Threshold
DTC P2032: Exhaust Gas Temperature (EGT) Sensor 2 Circuit Low Voltage
DTC P2033: Exhaust Gas Temperature (EGT) Sensor 2 Circuit High Voltage
Circuit Description
The exhaust gas temperature (EGT) sensors are variable resistors that measures the temperature of the exhaust gas. The EGT sensor 1 is located in the exhaust pipe after the catalytic convertor. The EGT 2 sensor is located in the exhaust gas particulate filter. The engine control module (ECM) supplies 5 volts to the EGT signal circuit and supplies a ground to the low reference circuit. The EGT sensor temperature information is used by the ECM during the exhaust gas particulate filter cleaning process.
The following table illustrates the difference between temperature, resistance, and voltage:
EGT | EGT Resistance | EGT Signal Voltage |
|---|---|---|
Cold | High | High |
Warm | Low | Low |
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The DTCs run continuously when the above condition is met. |
Conditions for Setting the DTC
P0544 03, P0545, and P2032
The ECM detects that the EGT sensor is less than 0.1 volt for greater than 0.5 seconds.
P0544 07, P0546, and P2033
The ECM detects that the EGT sensor is greater than 4.9 volts for greater than 0.5 seconds.
Action Taken When the DTC Sets
DTCs P0544, P0545, P0546, P2031, P2032, and P2033 are Type A DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0544, P0545, P0546, P2031, P2032, and P2033 are Type A DTCs.
Diagnostic Aids
| • | After starting the engine, the EGT sensor temperature should rise steadily, then stabilize after the engine reaches operating temperature. |
| • | If the vehicle has set overnight, the EGT sensor and the IAT sensor values should display within 3°C (5°F). |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, observe the DTC information with a scan tool. DTCs P0544 03, P0544 07, P0545, P0546, P2031 03, P2031 07, P2032, or P2033 should not set.
- 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
- Ignition OFF, and the MAIN fuse removed, disconnect the harness connector at the appropriate EGT sensor.
- Test for less than 5 ohms between the low reference circuit terminal 1 and ground.
- Install the MAIN fuse. Ignition ON, verify the scan tool EGT sensor parameter is at 5 volts.
- Install a 1A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool EGT sensor parameter is at 0 volts.
- If all circuits test normal, test or replace the EGT sensor.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
Important: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the sensor may be damaged.
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
Repair Verification
Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.
| ⇒ | If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning. |
