AutoCodes – Generic – P1378

P1378 Code - Fuel Injection Control Module Circuit Low Voltage

Quick Answer

The Engine Control Module (ECM) has detected an incorrect voltage level at the Fuel Injection Control Module (FICM) Common causes include Faulty Fuel Injection Control Module (FICM), Fuel Injection Control Module harness is open or shorted, Fuel Injection 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: P1378 indicates Fuel Injection Control Module Circuit Low Voltage.
Common causes: Common causes include Faulty Fuel Injection Control Module (FICM), Fuel Injection Control Module harness is open or shorted, Fuel Injection 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 12,366

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 Aug 16, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1378 Description

The Engine Control Module (ECM) has detected an incorrect voltage level at the Fuel Injection Control Module (FICM)

OBDII Code P1378 - Fuel Injection Control Module Circuit Low Voltage - AutoCodes.com — P1378 Code - Fuel Injection Control Module Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P1378?

Faulty Fuel Injection Control Module (FICM)
Fuel Injection Control Module harness is open or shorted
Fuel Injection Control Module circuit poor electrical connection
Faulty Battery or Charging system

How to Fix the DTC P1378?

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 P1378 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 P1378 code?

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Need Help with the Code?

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Information for Specific Makes

P1378 Audi — Cylinder 8 Ignition Circuit Short To Ground
P1378 Ford — Fuel Injection Control Module Circuit Low Voltage
P1378 Volkswagen — Cylinder 8 Ignition Circuit Short To Ground

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.