AutoCodes – Generic – P009C

P009C Code - Fuel Pressure Relief Control Circuit Low

Quick Answer

The Engine Control Module (ECM) uses the Fuel Rail Pressure (FRP) sensor to monitor the high side fuel pressure and the fuel rail pressure relief valve performance. Common causes include Faulty Fuel Pressure Relief Valve, Fuel Pressure Relief Valve harness is open or shorted, Fuel Pressure Relief Valve 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: P009C indicates Fuel Pressure Relief Control Circuit Low.
Common causes: Common causes include Faulty Fuel Pressure Relief Valve, Fuel Pressure Relief Valve harness is open or shorted, Fuel Pressure Relief Valve 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 3,271

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 Apr 09, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P009C Description

The Engine Control Module (ECM) uses the Fuel Rail Pressure (FRP) sensor to monitor the high side fuel pressure and the fuel rail pressure relief valve performance. The fuel rail pressure relief valve is designed to release fuel pressure in the event of an overpressure condition. This diagnostic looks for excessive fuel rail pressure decay to detect an open fuel rail pressure relief valve.

OBDII Code P009C - Fuel Pressure Relief Control Circuit Low - AutoCodes.com — P009C Code - Fuel Pressure Relief Control Circuit Low

What does this mean?

What are the Possible Causes of the DTC P009C?

Faulty Fuel Pressure Relief Valve
Fuel Pressure Relief Valve harness is open or shorted
Fuel Pressure Relief Valve circuit poor electrical connection

How to Fix the DTC P009C?

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 P009C 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 P009C code?

Need more information on how to fix the P009C code? Get Access to Factory Service Manuals

Need Help with the Code?

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Information for Specific Makes

P009C Chevrolet — Fuel Pressure Relief Control Circuit Low
P009C GMC — Fuel Pressure Relief Control Circuit Low

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.