AutoCodes – Chevrolet – P128C 2018 Chevrolet Silverado

P128C 2018 Chevrolet Silverado Code - Fuel Rail Temperature Sensor 1 Signal Message Counter Incorrect

Quick Answer

The fuel rail pressure sensor transmits fuel pressure and temperature information by serial data. Common causes include Faulty Fuel Rail Temperature Sensor 1, Fuel Rail Temperature Sensor 1 harness is open or shorted, Fuel Rail Temperature Sensor 1 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: P128C 2018 Chevrolet Silverado indicates Fuel Rail Temperature Sensor 1 Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Fuel Rail Temperature Sensor 1, Fuel Rail Temperature Sensor 1 harness is open or shorted, Fuel Rail Temperature Sensor 1 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 404

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 26, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P128C 2018 Chevrolet Silverado Description

The fuel rail pressure sensor transmits fuel pressure and temperature information by serial data. The fuel rail pressure sensor internal microprocessor allows 4 separate sensor outputs from one 3 wire sensor. The Engine Control Module (ECM) supplies the fuel rail pressure sensor with a 5 V reference circuit, a low reference circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the fuel rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages which are displayed on a scan tool as the voltage inputs from the Fuel Temperature Sensor, Fuel Rail Pressure Sensor and Fuel Rail Pressure Sensor 2.

OBDII Code P128C 2018 Chevrolet Silverado - Fuel Rail Temperature Sensor 1 Signal Message Counter Incorrect - AutoCodes.com — P128C 2018 Chevrolet Silverado Code - Fuel Rail Temperature Sensor 1 Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P128C 2018 Chevrolet Silverado?

Faulty Fuel Rail Temperature Sensor 1
Fuel Rail Temperature Sensor 1 harness is open or shorted
Fuel Rail Temperature Sensor 1 circuit poor electrical connection

How to Fix the DTC P128C 2018 Chevrolet Silverado?

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 P128C 2018 Chevrolet Silverado 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 P128C 2018 Chevrolet Silverado code?

Need more information on how to fix the P128C 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the 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 P128C 2018 Chevrolet Silverado Code

What does the OBDII code P128C mean on a 2018 Chevrolet Silverado?

The P128C code indicates an issue where the Fuel Rail Temperature Sensor 1 Signal Message Counter is incorrect, typically caused by communication or sensor-related problems.

What are the symptoms of code P128C in a 2018 Chevrolet Silverado?

Symptoms may include a check engine light, poor engine performance, hard starting, reduced fuel efficiency, or erratic engine behavior.

What causes the P128C code on a 2018 Chevrolet Silverado?

Common causes include a faulty fuel rail temperature sensor, wiring or connection issues, a malfunctioning ECM, or software glitches.

Can I drive my 2018 Chevrolet Silverado with the P128C code?

Driving with this code is not recommended as it may lead to poor performance or potential engine damage if fuel delivery is not properly monitored.

How do I diagnose the P128C code?

Diagnosis involves checking the fuel rail temperature sensor, inspecting the wiring and connectors for damage, and using a scan tool to monitor live data and communication errors.

How do I fix the P128C code on a 2018 Chevrolet Silverado?

Repairs may include replacing the fuel rail temperature sensor, repairing damaged wiring or connectors, or updating the ECM software if necessary.

How much does it cost to fix a P128C code?

Repair costs can vary, but replacing the fuel rail temperature sensor typically costs between $150 and $300, depending on parts and labor rates.

Can a bad ECM cause the P128C code?

Yes, a malfunctioning ECM or corrupted software can cause communication errors leading to the P128C code.

What tools are needed to troubleshoot the P128C code?

Youâ€™ll need an OBDII scan tool, a multimeter for testing wiring, and possibly a repair manual for your vehicle to locate components and wiring diagrams.

Is the P128C code specific to the 2018 Chevrolet Silverado?

While it is common in the 2018 Silverado, this code can appear in other GM vehicles with similar fuel rail temperature sensor systems.