* Turn Signal Multifunction Switch Replacement (See: Lighting and Horns/Sensors and Switches - Lighting and Horns/Turn Signal
Switch/Service and Repair/Turn Signal Multifunction Switch Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup, and programming
HVAC - Automatic
DTC B3933
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) 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)
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) Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC B3933 02
- Evaporator Air Temperature Sensor Short to Ground
DTC B3933 05
- Evaporator Air Temperature Sensor Short to Battery or Open
Circuit Description
The HVAC control module supplies the evaporator air temperature sensor with a low reference circuit and 5-volt signal circuit. The HVAC control
module determines the voltage drop across the sensor, which is proportional to temperature. As the air temperature increases, the sensor resistance
decreases and the voltage signal decreases. As the air temperature decreases, the sensor resistance increases and the voltage signal increases.
Conditions for Running the DTC
The ignition is turned ON.
Conditions for Setting the DTC
The HVAC control module detects the evaporator air temperature sensor signal circuit is less than -36锟斤拷C (-38锟斤拷F) or more than 215锟斤拷C (419锟斤拷F) for
more than 15 seconds.
Action Taken When the DTC Sets
The A/C compressor will be disabled.
Conditions for Clearing the DTC
* The DTC will become history if the HVAC control module no longer detects a failure.
* The history DTC will clear after 100 fault-free ignition cycles.
Reference Information
Schematic Reference
HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams/HVAC - Automatic) HVAC Schematics
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views) Component Connector End Views
Description and Operation
* Air Temperature Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air
Temperature Description and Operation) Air Temperature Description and Operation
* Air Delivery Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air Delivery
Description and Operation) Air Delivery Description and Operation
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing) Circuit Testing
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs) Connector Repairs
