2010 Cadillac Truck SRX FWD V6-3.0L Page 2002

2010 Cadillac Truck SRX FWD V6-3.0L Page 2002

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

1. Observe the DTC information with a scan tool. DTC P2177 or P2187 should not be set.

瀚慖f there are other DTCs set besides DTC P2177 or P2187 refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic

Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) to diagnosis the applicable DTC.

2. Ignition ON, observe the BARO pressure parameter and compare the reading on the scan tool to the barometric pressure table. Refer to

Altitude Versus Barometric Pressure (See: Powertrain Management/Computers and Control Systems/Specifications/Altitude Versus

Barometric Pressure).

瀚慖f the BARO pressure is not within the range specified for your altitude, refer to DTC P2227, P2228, or P2229 (LAU) ( See: P Code

Charts/P2227).

3. Engine at normal operating temperature, observe the Average Total Fuel Trim parameter with a scan tool. The Average Total Fuel Trim

should be between -22 to +23 %.

瀚慖f not within the specified range, verify none of the following conditions exist:

* A mass air flow sensor signal that is skewed-If the Short Term Fuel Trim parameter changes greater than 20 % when the MAF sensor is

disconnected, refer to DTC P0101 (LAU) (See: P Code Charts/P0101)DTC P0101 (LF1) (See: P Code Charts/P0101).

* The air intake system after the MAF sensor for vacuum leaks

* Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool) (See: Powertrain Management/Fuel Delivery and

Air Induction/Fuel/Testing and Inspection/Alcohol/Contaminants-in-Fuel Diagnosis (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)) and Fuel System Cleaning (See:

Powertrain Management/Fuel Delivery and Air Induction/Service and Repair).

* Splits, kinks, or improper connections at the vacuum hoses.

* The fuel system is operating lean. Refer to Fuel System Diagnosis (LF1 China) (See: Powertrain Management/Fuel Delivery and Air

Induction/Fuel Pump/Testing and Inspection/Fuel System Diagnosis (China))Fuel System Diagnosis (LF1 Except China) (See:

Powertrain Management/Fuel Delivery and Air Induction/Fuel Pump/Testing and Inspection/Fuel System Diagnosis (Except China))Fuel

System Diagnosis (LAU China) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Pump/Testing and Inspection/Fuel

System Diagnosis (China))Fuel System Diagnosis (LAU Except China) (See: Powertrain Management/Fuel Delivery and Air

Induction/Fuel Pump/Testing and Inspection/Fuel System Diagnosis (Except China)).

* Vacuum leaks at the intake manifold or throttle body

* Leaking crankcase ventilation system

* The engine control module grounds for being clean, tight, and in the correct locations

* A high engine oil level condition-A high engine oil level causes oil residue to form on the mass air flow sensor, causing a lean indication.

The MAF sensor does not need to be replaced.

* Vacuum leaks that only affect one bank of the engine-For example, the intake manifold, the injector O-rings.

* Lean injectors-Refer to Fuel Injector Solenoid Coil Test (LAU) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel

Injector/Testing and Inspection)Fuel Injector Solenoid Coil Test (LF1, LFW) (See: Powertrain Management/Fuel Delivery and Air

Induction/Fuel Injector/Testing and Inspection).

* Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust (See: Engine, Cooling and Exhaust/Exhaust

System/Testing and Inspection/Symptoms - Engine Exhaust).

* The heated oxygen sensor (HO2S) is installed securely and the electrical connector is not contacting the exhaust system.

* An engine mechanical condition-Refer to Symptoms - Engine Mechanical (See: Engine, Cooling and Exhaust/Engine/Testing and

Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Mechanical).

4. 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.

P2178

DTC P2178 or P2188

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