2010 Cadillac CTS Sedan AWD V6-3.6L Page 1024

2010 Cadillac CTS Sedan AWD V6-3.6L Page 1024



Circuit/System Testing



1. Ignition OFF, disconnect the harness connector at the B75B MAF/IAT sensor.



2. Ignition OFF, all vehicle systems OFF, this may take up to 2 minutes, test for less than 5 ohm between the low reference circuit terminal A or



terminal 2 and ground.



瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance, or for a short to voltage. If the circuit tests



normal, replace the K20 ECM.



3. Ignition ON, verify the scan tool IAT parameter is colder than -39掳C (-38掳F).



瀚慖f greater than the specified range, test the signal circuit terminal B or terminal 1 for a short to ground. If the circuit tests normal, replace



the K20 ECM.



Note: If the fuse in the jumper wire opens, the signal circuit is shorted to voltage and the sensor may be damaged.



4. Install a 3 A fused jumper wire between the signal circuit terminal B or terminal 1 and ground. Verify the scan tool IAT parameter is greater



than 149掳C (300掳F).



瀚慖f less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace



the K20 ECM.



5. If all circuits test normal, test or replace the B75B MAF/IAT sensor.



Component Testing



Measure and record the resistance of the B66 IAT sensor at various ambient temperatures, then compare those measurements to the Temperature



Versus Resistance - Intake Air Temperature Sensor (See: Powertrain Management/Computers and Control Systems/Specifications) table.



Repair Instructions



Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.



* 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 ECM replacement, setup, and programming



P0116



DTC P0116 (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 Descriptor



DTC P0116



- Engine Coolant Temperature (ECT) Sensor Performance



Diagnostic Fault Information



Typical Scan Tool Data

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