2010 Cadillac CTS Sedan AWD V6-3.6L Page 1837
Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (without Special
Tool) (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics/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
瀚慖f you find any of the above conditions, repair as necessary.
Warning: Refer to Road Test Warning (See: Service Precautions/Technician Safety Information/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 (See: Verification Tests) after completing the diagnostic procedure.
P2097
DTC P2097 or P2099
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P2097
- Post Catalyst Fuel Trim System High Limit Bank 1
DTC P2099
- Post Catalyst Fuel Trim System High 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 P2097 or P2099 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掳C (482掳F).
* DTC P2097 and P2099 run continuously when the conditions above have been met for greater than 130 seconds.
Conditions for Setting the DTC
The rich correction limit for a condition causing a lean 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 P2097 and P2099 are Type B DTCs.
