P0642 2014 GMC Sierra Code - 5 Volt Reference 1 Circuit Low Voltage
Quick Answer
The Engine Control Module (ECM) has four (4) internal 5 Volt reference circuits (Some models have two (2) internal 5 Volt reference circuits). Common causes include Faulty Sensor on 5 Volt circuit, Sensor on 5 Volt circuit harness is open or shorted, Sensor on 5 Volt 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
- P0642 2014 GMC Sierra indicates 5 Volt Reference 1 Circuit Low Voltage.
- Common causes
- Common causes include Faulty Sensor on 5 Volt circuit, Sensor on 5 Volt circuit harness is open or shorted, Sensor on 5 Volt 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.
Code P0642 2014 GMC Sierra Description
What are the Possible Causes of the DTC P0642 2014 GMC Sierra?
- Faulty Sensor on 5 Volt circuit
- Sensor on 5 Volt circuit harness is open or shorted
- Sensor on 5 Volt circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0642 2014 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.
Code Tech Notes
The 5 Volt reference 1 circuit provides 5 Volt to the following sensors: (Some models may have different sensors, please consult the factory service manual for the list of sensors for your model and year)
- Air conditioning (A/C) refrigerant pressure sensor
- Camshaft position sensor
- Engine oil pressure sensor
- Fuel pressure sensor
- Fuel rail pressure sensor
- Fuel tank pressure sensor
- Multifunction intake air sensor
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0642 2014 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 P0642 2014 GMC Sierra code?
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Frequently Asked Questions about P0642 2014 GMC Sierra Code
What does the OBDII code P0642 mean on a 2014 GMC Sierra?
P0642 indicates a "5 Volt Reference 1 Circuit Low Voltage" issue, meaning the ECU has detected a problem with one of its 5-volt reference circuits, which supply power to certain sensors.
What are the common symptoms of code P0642 on a 2014 GMC Sierra?
Symptoms may include poor engine performance, erratic sensor readings, a check engine light, difficulty starting, or the engine stalling.
What causes the P0642 code to appear on a 2014 GMC Sierra?
Common causes include a shorted sensor, damaged wiring, corroded connectors, a malfunctioning ECU, or a ground issue affecting the 5-volt reference circuit.
Which sensors may be affected by a P0642 code on a 2014 GMC Sierra?
Sensors dependent on the 5-volt reference circuit include the throttle position sensor (TPS), manifold absolute pressure (MAP) sensor, and fuel rail pressure sensor, among others.
How can I diagnose the P0642 code on a 2014 GMC Sierra?
Begin by inspecting the wiring and connectors for damage or corrosion. Use a multimeter to check the 5-volt reference circuit at affected sensors and trace the fault to the root cause.
Can a shorted sensor cause the P0642 code on a 2014 GMC Sierra?
Yes, a shorted sensor can draw excessive current or cause a low voltage condition, triggering the P0642 code.
Is it safe to drive a 2014 GMC Sierra with the P0642 code?
Driving with this code is not recommended, as it may lead to poor engine performance or stalling, which could create a safety risk.
How much does it cost to repair the P0642 code on a 2014 GMC Sierra?
Repair costs vary depending on the root cause but may range from $50 for a simple wiring repair to $500 or more if a sensor or ECU replacement is required.
Can clearing the code fix the P0642 issue on a 2014 GMC Sierra?
Clearing the code won't fix the underlying problem. The issue must be diagnosed and repaired to prevent the code from returning.
What tools are needed to troubleshoot the P0642 code on a 2014 GMC Sierra?
You’ll need an OBDII scanner, a multimeter, and possibly a wiring diagram to diagnose the issue and identify the faulty component or circuit.
Discuss the causes and fixes for P0642 2014 GMC Sierra OBDII Code
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