DTC P2084 or P2085 - LPL or LPV
Diagnostic Instructions
DTC Descriptor
DTC P2084 00: Exhaust Gas Temperature
Sensor 2 Performance
DTC P2085 00: Exhaust Gas Temperature
Sensor 2 Circuit Intermittent
Circuit/System Description
The exhaust gas temperature sensors are variable resistors that
measure the temperature of the exhaust gas. The exhaust gas
temperature sensor 1 is located in the exhaust pipe after the
catalyst. The exhaust gas temperature 2 sensor is located in
the exhaust gas particulate filter. The engine control
module (ECM) supplies 5 V to the exhaust gas temperature
signal circuit and supplies a ground to the low reference circuit.
The exhaust gas temperature 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:
|
Exhaust Gas Temperature
|
Exhaust Gas Temperature Resistance
|
Exhaust Gas Temperature Signal Voltage
|
|
Cold
|
High
|
High
|
|
Warm
|
Low
|
Low
|
Conditions for Running the DTC
| • |
The DTCs run continuously when the above condition
is met. |
Conditions for Setting the DTC
The ECM detects that the exhaust gas temperature sensor signal
is not plausible.
Action Taken When the DTC Sets
DTCs P2084 and P2085 are Type C DTCs.
Conditions for Clearing the DTC
DTCs P2084 and P2085 are Type C DTCs.
Diagnostic Aids
| • |
After starting the engine, the exhaust gas
temperature sensor temperature should rise steadily, then stabilise
after the engine reaches operating temperature. |
| • |
If the vehicle has sat overnight, the exhaust gas
temperature sensor and the intake air temperature (IAT) sensor
values should display within 3°C (5°F). |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
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. DTC P2084 and DTC P2085 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, disconnect the harness connector at the
B131B Exhaust Temperature Sensor 2.
- Test for less than 5 Ω between the low reference
circuit terminal 1 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 K20 Engine Control Module. |
- Disconnect the harness connector at the cooling
fan.
- Ignition ON, verify the scan tool Exhaust Gas
Temperature Sensor 2 parameter is at 5 V.
| ⇒ |
If less than the specified range, test the signal
circuit for a short to ground. If the circuit tests normal, replace
the K20 Engine Control Module. |
Note: If the fuse in the jumper
wire opens, the signal circuit is shorted to a voltage and the
sensor may be damaged.
- Install a 1 A fused jumper wire between the
signal circuit terminal 2 and ground. Verify the scan tool
Exhaust Gas Temperature Sensor 2 parameter is at
0 V.
| ⇒ |
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 K20 Engine Control
Module. |
- If all circuits test normal, test or replace the
B131B Exhaust Temperature Sensor 2.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
