AutoCodes – Generic – P1234

P1234 Code - Fuel Pump Driver Module Disabled Or Off Line

Quick Answer

The Powertrain Control Module (PCM) monitors the Fuel Pump Monitor (FPM) circuit from the Fuel Pump Driver Module (FPDM). Common causes include Inertia fuel shutoff (IFS) switch needs to be reset, Faulty Fuel Pump Driver Module (FPDM), Fuel Pump Driver Module (FPDM) harness is open or shorted. 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: P1234 indicates Fuel Pump Driver Module Disabled Or Off Line.
Common causes: Common causes include Inertia fuel shutoff (IFS) switch needs to be reset, Faulty Fuel Pump Driver Module (FPDM), Fuel Pump Driver Module (FPDM) harness is open or shorted.
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 39,325

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 Jul 20, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1234 Description

The Powertrain Control Module (PCM) monitors the Fuel Pump Monitor (FPM) circuit from the Fuel Pump Driver Module (FPDM). With the key on, the FPDM continuously sends a duty cycle signal to the PCM through the FPM circuit. The test fails if the PCM stops receiving the duty cycle signal.

OBDII Code P1234 - Fuel Pump Driver Module Disabled Or Off Line - AutoCodes.com — P1234 Code - Fuel Pump Driver Module Disabled Or Off Line

What does this mean?

What are the Possible Causes of the DTC P1234?

Inertia fuel shutoff (IFS) switch needs to be reset
Faulty Fuel Pump Driver Module (FPDM)
Fuel Pump Driver Module (FPDM) harness is open or shorted
Fuel Pump Driver Module (FPDM) circuit poor electrical connection
Faulty Inertia Fuel Shutoff (IFS) switch
Faulty Powertrain Control Module (PCM)

How to Fix the DTC P1234?

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 P1234 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 P1234 code?

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Need Help with the Code?

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Information for Specific Makes

P1234 BMW — Fuel Pump Relay Activation
P1234 Buick — Injector Circuit Cylinder 5 Intermittent
P1234 Cadillac — Injector Circuit Cylinder 5 Intermittent
P1234 Chevrolet — Injector Circuit Cylinder 5 Intermittent
P1234 Chrysler — Pedal Position Sensor 2 CKT Plausibility
P1234 Dodge — Pedal Position Sensor 2 CKT Plausibility
P1234 Ford — Fuel Pump Driver Module Disabled Or Off Line
P1234 GMC — Injector Circuit Cylinder 5 Intermittent
P1234 Jeep — Pedal Position Sensor 2 CKT Plausibility
P1234 Lincoln — Fuel Pump Driver Module Disabled Or Off Line
P1234 Mazda — Fuel Pump Driver Module Disabled Or Off Line
P1234 Mercury — Fuel Pump Driver Module Disabled Or Off Line
P1234 MINI — Fuel Pump Relay Activation
P1234 Mitsubishi — Sub Throttle Position Sensor Plausibility

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.