AutoCodes – GMC – P034B 2015 GMC Sierra

P034B 2015 GMC Sierra Code - Crankshaft Position Sensor Crankshaft Direction Incorrect

Quick Answer

The Engine Control Module (ECM) monitors the speed and the direction of rotation of the crankshaft during an autostop event and memorizes the crankshaft angle at which the engine stopped to be able to start the engine quicker. Common causes include Faulty Crankshaft Position Sensor, Crankshaft Position Sensor harness is open or shorted, Crankshaft Position 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: P034B 2015 GMC Sierra indicates Crankshaft Position Sensor Crankshaft Direction Incorrect.
Common causes: Common causes include Faulty Crankshaft Position Sensor, Crankshaft Position Sensor harness is open or shorted, Crankshaft Position 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 164

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 Sep 23, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P034B 2015 GMC Sierra Description

The Engine Control Module (ECM) monitors the speed and the direction of rotation of the crankshaft during an autostop event and memorizes the crankshaft angle at which the engine stopped to be able to start the engine quicker. The Diagnostic Trouble Code (DTC) will be set when the direction of rotation of the crankshaft has changed more than 3 times within 10 s.

OBDII Code P034B 2015 GMC Sierra - Crankshaft Position Sensor Crankshaft Direction Incorrect - AutoCodes.com — P034B 2015 GMC Sierra Code - Crankshaft Position Sensor Crankshaft Direction Incorrect

What does this mean?

What are the Possible Causes of the DTC P034B 2015 GMC Sierra?

Faulty Crankshaft Position Sensor
Crankshaft Position Sensor harness is open or shorted
Crankshaft Position Sensor circuit poor electrical connection

How to Fix the DTC P034B 2015 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 P034B 2015 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 P034B 2015 GMC Sierra code?

Need more information on how to fix the P034B 2015 GMC Sierra code? Get Access to Factory Service Manuals

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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 P034B 2015 GMC Sierra Code

1. What does the OBDII code P034B mean on a 2015 GMC Sierra?

P034B indicates an issue with the crankshaft position sensor where it is reporting incorrect crankshaft direction data to the engine control module (ECM).

2. What are the common symptoms of a P034B code on a 2015 GMC Sierra?

Symptoms may include difficulty starting, engine misfires, reduced power, poor fuel efficiency, or the engine stalling.

3. What causes the P034B code to appear on a 2015 GMC Sierra?

Common causes include a faulty crankshaft position sensor, damaged wiring or connectors, a misaligned timing chain or belt, or an ECM malfunction.

4. Can I drive my 2015 GMC Sierra with the P034B code?

It is not recommended to drive the vehicle for extended periods with this code, as it can lead to engine performance issues or further damage.

5. How is the P034B code diagnosed on a 2015 GMC Sierra?

A mechanic will use a scan tool to verify the code, inspect the crankshaft position sensor, check the wiring and connectors, and possibly test the ECM for faults.

6. How do I fix the P034B code on my 2015 GMC Sierra?

Repairs may include replacing the crankshaft position sensor, repairing damaged wiring, realigning the timing chain or belt, or reprogramming/updating the ECM.

7. How much does it cost to fix the P034B code on a 2015 GMC Sierra?

The cost can vary, but replacing a crankshaft position sensor typically ranges from $150 to $300, including parts and labor. Additional repairs may increase the cost.

8. Can a weak battery cause the P034B code on a 2015 GMC Sierra?

Yes, a weak or failing battery can lead to electrical issues that may trigger this code, as the sensor and ECM rely on stable voltage.

9. How can I prevent the P034B code from recurring on my 2015 GMC Sierra?

Regular maintenance, such as inspecting the timing components, ensuring proper sensor installation, and keeping the electrical system in good condition, can help prevent this code.

10. Is the P034B code related to the camshaft position sensor?

No, the P034B code specifically pertains to the crankshaft position sensor and its ability to detect crankshaft direction, though issues with related timing components could indirectly affect both sensors.