2010 Cadillac CTS Sedan AWD V6-3.6L Page 1003

2010 Cadillac CTS Sedan AWD V6-3.6L Page 1003

* 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 P0100

- Mass Air Flow (MAF) Sensor Circuit

DTC P0102

- Mass Air Flow (MAF) Sensor Circuit Low Frequency

DTC P0103

- Mass Air Flow (MAF) Sensor Circuit High Frequency

Diagnostic Fault Information

Circuit/System Description

The mass air flow (MAF) sensor is located in the air intake duct. The MAF sensor is an airflow meter that measures the amount of air that enters the

engine. The MAF sensor uses a hot film that is cooled by air flowing past the sensing film as air enters the engine. The amount of cooling is

proportional to the amount of the air flow. As the air flow increases, more current is required in order to maintain the hot film at a constant

temperature. The engine control module (ECM) uses the MAF sensor in order to provide the correct fuel delivery for all operating conditions. The

intake air temperature (IAT) sensor is integrated into the MAF sensor.

Conditions for Running the DTC

* The ignition is ON, or the engine is operating.

* The ignition voltage is greater than 10.5 V.

* DTC P0100, P0102 and P0103 run continuously once the above conditions are met for 200 mS.

Conditions for Setting the DTC

P0100

The ECM detects that the MAF sensor signal is 0.0 Hz.

P0102

The ECM detects that the MAF sensor signal is less than 1433 Hz.

P0103

The ECM detects that the MAF sensor signal is greater than 12,346 Hz.

Action Taken When the DTC Sets

DTCs P0100, P0102, and P0103 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0100, P0102, and P0103 are Type B DTCs.

Diagnostic Aids

* Inspect the harness of the B75B MAF/IAT sensor to verify that it is not routed too close to the following components:

- The secondary ignition wires or coils