P1474 2018 GMC Sierra Code - Particulate Matter Sensor Electrode Supply Circuit
Quick Answer
The Particulate Matter (PM) sensor monitors the amount of the particulates (soot) in the diesel exhaust gas exiting the tailpipe. Common causes include Faulty Exhaust Particulate Matter Sensor, Exhaust Particulate Matter Sensor harness is open or shorted, Exhaust Particulate Matter 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
- P1474 2018 GMC Sierra indicates Particulate Matter Sensor Electrode Supply Circuit.
- Common causes
- Common causes include Faulty Exhaust Particulate Matter Sensor, Exhaust Particulate Matter Sensor harness is open or shorted, Exhaust Particulate Matter 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.
Code P1474 2018 GMC Sierra Description
The operation of the PM Sensor is based on the electrical conductivity characteristic of the diesel particulate. As the exhaust gas flows over the sensing element, soot is absorbed in the combs between the electrodes, eventually creating a conductive path. When the path is formed, it generates a current based on the voltage being applied to the element. The measurement process continues until a preset current value is reached. To avoid misleading readings, the sensor performs a regeneration where the soot is cleaned off by heating up the element before the measurement phase begins. The amount of regenerations is based on vehicle strategy; when the calibrated number of regenerations is reached, the cumulative current readings are used to determine the amount of soot concentration in the exhaust gas which in turn determines the collection efficiency of the Diesel Particulate Filter (DPF).
The Diagnostic Trouble Code (DTC) will be set when the particular matter sensor control unit detects a fault in the particulate matter sensor circuitry.
What are the Possible Causes of the DTC P1474 2018 GMC Sierra?
- Faulty Exhaust Particulate Matter Sensor
- Exhaust Particulate Matter Sensor harness is open or shorted
- Exhaust Particulate Matter Sensor circuit poor electrical connection
How to Fix the DTC P1474 2018 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 P1474 2018 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.
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Frequently Asked Questions about P1474 2018 GMC Sierra Code
What does the OBDII code P1474 mean on a 2018 GMC Sierra?
Code P1474 indicates an issue with the particulate matter (PM) sensor electrode supply circuit, which monitors soot levels in the exhaust system.
What are the symptoms of the P1474 code in a 2018 GMC Sierra?
Symptoms may include an illuminated check engine light, reduced engine performance, poor fuel efficiency, and possible issues with the exhaust system.
What causes the P1474 code to appear on a 2018 GMC Sierra?
Common causes include a faulty particulate matter sensor, damaged wiring or connectors in the sensor circuit, or a malfunctioning engine control module (ECM).
Can I drive my 2018 GMC Sierra with the P1474 code?
Driving with this code is not recommended, as it may lead to further damage to the exhaust system or reduced engine performance over time.
How do I diagnose the P1474 code on a 2018 GMC Sierra?
Diagnosis typically involves checking the particulate matter sensor, inspecting the wiring and connectors for damage, and using a scan tool to monitor sensor data and circuit performance.
What tools are needed to troubleshoot the P1474 code?
You’ll need an OBDII scan tool, a multimeter to check electrical continuity, and possibly a repair manual for detailed wiring diagrams.
How is the P1474 code repaired on a 2018 GMC Sierra?
Repairs may include replacing the particulate matter sensor, repairing or replacing damaged wiring or connectors, or reprogramming/updating the ECM if necessary.
How much does it cost to fix the P1474 code on a 2018 GMC Sierra?
The cost varies but typically includes $200–$500 for a new particulate matter sensor plus labor costs, depending on the mechanic or dealership rates.
Can a dirty particulate filter cause the P1474 code?
While a dirty diesel particulate filter (DPF) may not directly cause this code, it can lead to related issues that affect the PM sensor's operation.
Is the P1474 code covered under warranty for a 2018 GMC Sierra?
This depends on your vehicle’s warranty terms. Emissions-related components like the particulate matter sensor may be covered under the emissions warranty.
Discuss the causes and fixes for P1474 2018 GMC Sierra OBDII Code
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