2010 Cadillac CTS Sedan AWD V6-3.6L Page 1000
瀚慖f less than the specified range, test the signal circuit for an open/high resistance or a short to ground. If the circuit/connections test
normal, replace the K20 ECM.
瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit/connections test normal, replace the K20
ECM.
7. Ignition OFF, connect the red lead of the J 38522 to the signal circuit terminal A at the B75B MAF/IAT sensor harness connector. Connect
the battery voltage supply to B+, and ground the black lead.
8. Set the J 38522 Signal switch to 5 V, the Frequency switch to 5K, and the Duty Cycle switch to Normal.
9. Ignition ON, observe the scan tool MAF Sensor frequency parameter. The parameter should be between 4,950-5,025 Hz.
瀚慖f the parameter is not within the specified range, replace the K20 ECM.
10. If all circuits/connections test normal, replace the B75B MAF/IAT sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LLT) (See: Powertrain Management/Computers and Control
Systems/Air Temperature Sensor ( Ambient / Intake )/Service and Repair)Mass Airflow Sensor with Intake Air Temperature Sensor
Replacement (LSA) (See: Powertrain Management/Computers and Control Systems/Air Temperature Sensor ( Ambient / Intake )/Service
and Repair)Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LF1) (See: Powertrain Management/Computers and
Control Systems/Air Temperature Sensor ( Ambient / Intake )/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for engine control module replacement, setup, and
programming
P0102
DTC P0100-P0103 (w/LLT)
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 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
