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P2098




DTC P2096 or P2098

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 P2096
- Post Catalyst Fuel Trim System Low Limit Bank 1

DTC P2098
- Post Catalyst Fuel Trim System Low Limit Bank 2

Circuit Description

Fuel trim bias is used to keep the post catalyst air/fuel ratio within a predetermined range. This allows optimal catalyst efficiency under light load conditions at a steady cruise. The engine control module (ECM) constantly monitors how lean or rich the fuel trim bias is commanded, to determine if the fuel trim bias is greater than a calibrated amount.

Conditions for Running the DTC

* Before the ECM can report DTC P2096 or P2098 failed, DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0056, P0057, P0058, P013A, P013C, P013E, P0130, P0131, P0132, P0133, P0135, P0137, P0138, P014A, P0140, P0141, P0150, P0151, P0152, P0153, P0155, P0157, P0158, P0160, P0161, P2232, P2235, P2270, P2271, P2272, and P2273 must run and pass.
* DTC P0100, P0101, P0102, P0103, P0420, P0430, P0442, P0443, P0455, P0458, P0459, P2177, P2178, P2179, P2180, P2187, P2188, P2189 or P2190 is not set.
* The engine speed is 1,280-3,480 RPM.
* The engine load is 17-65 percent and steady.
* The closed loop fuel control is active for greater than 1 second.
* The calculated exhaust gas temperature is greater than 250°C (482°F).
* DTC P2096 and P2098 run continuously when the conditions above have been met for greater than 130 seconds.

Conditions for Setting the DTC

The lean correction limit for a condition causing a rich air/fuel ratio has been exceeded for greater than 4 seconds or for a cumulative of 30 seconds.

Action Taken when the DTC Sets

DTCs P2096 and P2098 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2096 and P2098 are Type B DTCs.

Diagnostic Aids

An HO2S will not cause this DTC to set without the occurrence of circuit related HO2S DTCs. Do not replace an HO2S to address this DTC.

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
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 (Programming and Relearning)for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool DTC information. Verify there is no other HO2S or fuel trim DTC set.

If any other HO2S or fuel trim DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).

2. Verify that none of the following conditions exist:

* Rich fuel injectors-Refer to Fuel Injector Solenoid Coil Test (Fuel Injector Solenoid Coil Test).
* High fuel system pressure-Refer to Fuel System Diagnosis (Fuel System Diagnosis).
* Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool) (Alcohol/Contaminants-In-Fuel Diagnosis (Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool) (Alcohol/Contaminants-In-Fuel Diagnosis (Without Special Tool)).
* Fuel saturation of the evaporative emissions (EVAP) canister
* Stuck open or leaking EVAP purge valve
* Restricted exhaust
* Incorrect PCV system operation

If you find any of the above conditions, repair as necessary.

Warning: Refer to Road Test Warning (Road Test Warning).


Note: A road load condition is necessary to obtain closed loop.

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.

Repair Instructions

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