AutoCodes – GMC – P101B 2017 GMC Sierra

P101B 2017 GMC Sierra Code - Glow Plug Control Module Temperature Sensor 2 Circuit Low Voltage

Quick Answer

The Glow Plug Control Module (GPCM) has the ability to perform internal diagnostics for the temperature sensor circuit. Common causes include Faulty Glow Plug Control Module (GPCM), Glow Plug Control Module harness is open or shorted, Glow Plug Control Module 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: P101B 2017 GMC Sierra indicates Glow Plug Control Module Temperature Sensor 2 Circuit Low Voltage.
Common causes: Common causes include Faulty Glow Plug Control Module (GPCM), Glow Plug Control Module harness is open or shorted, Glow Plug Control Module 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 219

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Oct 01, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P101B 2017 GMC Sierra Description

The Glow Plug Control Module (GPCM) has the ability to perform internal diagnostics for the temperature sensor circuit. The GPCM monitors the internal temperature sensor voltage and if the voltage is less than 0.21 V or greater than 4.94 V. The GPCM will send a message to the Engine Control Module (ECM) to set the appropriate Diagnostic Trouble Code (DTC). A DTC is detected when one of the GPCM temperature sensors voltage falls outside the calibrated threshold for greater than 1.3 s.

OBDII Code P101B 2017 GMC Sierra - Glow Plug Control Module Temperature Sensor 2 Circuit Low Voltage - AutoCodes.com — P101B 2017 GMC Sierra Code - Glow Plug Control Module Temperature Sensor 2 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P101B 2017 GMC Sierra?

Faulty Glow Plug Control Module (GPCM)
Glow Plug Control Module harness is open or shorted
Glow Plug Control Module circuit poor electrical connection

How to Fix the DTC P101B 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 P101B 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 P101B 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 P101B 2017 GMC Sierra Code

What does the P101B code mean on a 2017 GMC Sierra?

The P101B code indicates a problem with the Glow Plug Control Module Temperature Sensor 2 Circuit, specifically detecting low voltage in the circuit.

What are the symptoms of a P101B code?

Common symptoms include the check engine light turning on, reduced engine performance, difficulty starting in cold weather, and potential issues with the glow plug system.

What causes the P101B code to appear?

The code can be triggered by a faulty temperature sensor, damaged wiring or connectors, a failed glow plug control module, or corrosion in the circuit.

Can I drive my 2017 GMC Sierra with a P101B code?

While the truck may still be drivable, ignoring the code can lead to issues with cold starts and reduced engine efficiency. Itâ€™s best to address the issue promptly.

How do I diagnose the P101B code?

Start by checking the wiring and connections to the temperature sensor for damage or corrosion. Use a multimeter to test the sensor and inspect the glow plug control module for faults.

What tools are needed to fix the P101B code?

Common tools include a multimeter for testing voltage, a code scanner for diagnostics, and basic hand tools for inspecting and replacing components.

How much does it cost to repair a P101B code?

Repair costs vary but typically involve replacing the temperature sensor ($50â€“$150) or repairing wiring. Labor costs depend on the shop and region.

Can a bad glow plug cause the P101B code?

While the code specifically refers to the temperature sensor circuit, issues with the glow plug system, such as a faulty control module, may indirectly cause the problem.

How do I reset the P101B code after repairs?

Use an OBDII scanner to clear the code after fixing the underlying issue. If the problem persists, the code may reappear.

Is the P101B code common in GMC Sierras?

This code is not overly common but can occur in diesel models where the glow plug system is critical for cold starts. Regular maintenance can help prevent it.