AutoCodes – GMC – B3933 2017 GMC Sierra

B3933 2017 GMC Sierra Code - Air Conditioning Evaporator Temperature Sensor Circuit

Quick Answer

The air temperature sensors are a 2-wire negative temperature coefficient thermistor. Common causes include Faulty Air Conditioning Evaporator Temperature Sensor, Air Conditioning Evaporator Temperature Sensor harness is open or shorted, Air Conditioning Evaporator Temperature Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B3933 2017 GMC Sierra indicates Air Conditioning Evaporator Temperature Sensor Circuit.
Common causes: Common causes include Faulty Air Conditioning Evaporator Temperature Sensor, Air Conditioning Evaporator Temperature Sensor harness is open or shorted, Air Conditioning Evaporator Temperature Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 748

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 17, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3933 2017 GMC Sierra Description

The air temperature sensors are a 2-wire negative temperature coefficient thermistor. This sensor operates using signal and low reference circuits. As the air temperature surrounding the sensor increases, the sensor resistance decreases. The sensor is capable of reading temperatures ranging from -40 to +80°C (-40 to +176°F), with a signal voltage between 0-5 V. If the Heating, Ventilation, and Air Conditioning (HVAC) Control Module detects a malfunctioning sensor the software uses a default air temperature value. The default action ensures that the HVAC system can adjust the inside air temperature near the desired temperature until the condition is corrected. The Diagnostic Trouble Code (DTC) sets when the input signal is out of range. The HVAC Control Module detects a voltage greater than 4.9 V on the temperature signal circuit.

OBDII Code B3933 2017 GMC Sierra - Air Conditioning Evaporator Temperature Sensor Circuit - AutoCodes.com — B3933 2017 GMC Sierra Code - Air Conditioning Evaporator Temperature Sensor Circuit

What does this mean?

What are the Possible Causes of the DTC B3933 2017 GMC Sierra?

Faulty Air Conditioning Evaporator Temperature Sensor
Air Conditioning Evaporator Temperature Sensor harness is open or shorted
Air Conditioning Evaporator Temperature Sensor circuit poor electrical connection
Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module

How to Fix the DTC B3933 2017 GMC Sierra?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3933 2017 GMC Sierra code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B3933 2017 GMC Sierra code?

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B3933 2017 GMC Sierra Code

1. What does the OBDII code B3933 mean on a 2017 GMC Sierra?

The B3933 code indicates an issue with the Air Conditioning Evaporator Temperature Sensor Circuit, which monitors the temperature of the evaporator to prevent freezing.

2. What are the common symptoms of code B3933 in a 2017 GMC Sierra?

Symptoms may include the air conditioning not functioning properly, poor cooling performance, or the A/C system shutting off unexpectedly.

3. What causes the B3933 code to appear on a 2017 GMC Sierra?

Common causes include a faulty evaporator temperature sensor, damaged wiring or connectors in the sensor circuit, or an issue with the HVAC control module.

4. How can I diagnose the B3933 code on my GMC Sierra?

Start by inspecting the evaporator temperature sensor and its wiring for damage or disconnection. Use a scan tool to read real-time temperature sensor data and check for irregular readings.

5. Can I drive my 2017 GMC Sierra with the B3933 code active?

Yes, but the air conditioning system may not work correctly, which could lead to discomfort in hot weather or potential long-term issues if left unresolved.

6. How do I fix the B3933 code on a 2017 GMC Sierra?

Repairs may involve replacing the evaporator temperature sensor, repairing damaged wiring or connectors, or reprogramming or replacing the HVAC control module if necessary.

7. What tools are needed to repair the B3933 code?

You may need a scan tool or OBDII code reader, a multimeter to test the wiring, and basic hand tools to access and replace the sensor if required.

8. How much does it cost to repair the B3933 code on a GMC Sierra?

Repair costs can vary. Replacing the evaporator temperature sensor typically costs $100-$300, while wiring repairs or module replacement may increase the cost.

9. Can a B3933 code be cleared without fixing the issue?

You can clear the code temporarily with a scan tool, but it will likely return if the underlying issue is not resolved.

10. Is the B3933 code specific to GMC vehicles?

No, while it appears on GMC vehicles like the Sierra, the code can also be found in other vehicles with similar HVAC systems. Always consult your vehicle's manual for specifics.