Diagnostic Instructions
DTC Descriptor
DTC P2084: Exhaust Gas Temperature (EGT) Sensor 2 Performance
Circuit/System Description
The engine control module (ECM) supplies 5 volts to the DOC exhaust gas temperature sensor on the 5-volt reference circuit. The ECM also provides a ground on the low reference circuit. The DOC exhaust gas temperature sensor provides a signal
to the ECM on the DOC exhaust gas temperature signal circuit which is relative to the pressure changes in the manifold. The ECM should detect a low signal voltage at a DOC exhaust gas temperature, such as low engine load. The ECM should detect high signal voltage
at a high DOC exhaust gas temperature, such as high engine load. The ECM monitors the DOC exhaust gas temperature sensor signal for voltage outside the normal range of the DOC exhaust gas temperature sensor.
Conditions for Running the DTC
| • | The following conditions are met for 6 seconds: |
| - | The battery voltage is between 10-16 volts. |
| - | The ignition is ON for longer than 2 seconds. |
| - | The engine speed is less than 2,550 RPM. |
| - | The engine speed does not vary more than 50 RPM. |
| - | The boost pressure does not vary more than 50 kPa. |
| - | The engine coolant temperature (ECT) is between -7 and +92°C (+19 and +198°F). |
| - | The fuel temperature is between -40 and +75°C (-40 and +167°F). |
| • | The following conditions are met: |
| - | The DPF status is zero without the regeneration event. |
| - | The intake throttle position is less than 55 percent. |
| - | The VNT control is normal mode. |
| - | The exhaust throttle command is OFF. |
| - | The exhaust brake command is OFF. |
| - | The DPF differential pressure is between -10 and +20 kPa. |
Conditions for Setting the DTC
The ECM detects DOC exhaust gas temperature error.
Action Taken When the DTC Sets
DTC P2084 is a Type A DTC.
Conditions for Clearing the DTC
DTC P2084 is a Type A DTC.
Diagnostic Aids
Inspect for any recent engine mechanical repairs. An incorrectly installed Pre. EGR cooler exhaust gas temperature sensor will cause this DTC to set.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Testing
Important: You must perform Circuit/System Verification before proceeding with Circuit/System Testing.
- Ignition OFF, disconnect the harness connector at the DOC exhaust gas temperature sensor.
- Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal A and ground.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
- Ignition ON, verify the scan tool DOC exhaust gas temperature parameter is less than 1°C (34°F).
| ⇒ | If greater than the specified range, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the ECM. |
- Install a 3-amp fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool DOC exhaust gas temperature parameter is more than 950°C (1,742°F).
| ⇒ | If less 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. |
| ⇒ | If all circuits test normal, test or replace the exhaust gas temperature sensor 1. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
