Engine-CodesGMC – P0656 GMC

P0656 GMC Code - Fuel Level Output Circuit Malfunction

Quick Answer

The P0656 GMC code indicates a Fuel Level Output Circuit Malfunction. Common causes include Faulty fuel level sensor, Damaged wiring or connectors in the sensor circuit, Corrosion or debris in the fuel tank affecting sensor readings. 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
P0656 GMC indicates Fuel Level Output Circuit Malfunction.
Common causes
Common causes include Faulty fuel level sensor, Damaged wiring or connectors in the sensor circuit, Corrosion or debris in the fuel tank affecting sensor readings.
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.
Table of contents Created and updated by William Orellana on Sep 12, 2024
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Code P0656 GMC Description

The P0656 GMC code indicates a Fuel Level Output Circuit Malfunction. This means that there is a problem with the fuel level sensor circuit, which is responsible for sending information about the fuel level in the tank to the vehicle's engine control module (ECM). The ECM uses this information to calculate fuel consumption and adjust the engine's performance accordingly.

OBDII Code P0656 GMC - Fuel Level Output Circuit Malfunction
P0656 GMC Code - Fuel Level Output Circuit Malfunction

Common Causes of P0656 GMC

  1. Faulty fuel level sensor
  2. Damaged wiring or connectors in the sensor circuit
  3. Corrosion or debris in the fuel tank affecting sensor readings
  4. Malfunctioning ECM

Symptoms of P0656 GMC

  1. Inaccurate fuel level readings on the dashboard
  2. Poor fuel economy
  3. Engine stalling or misfiring
  4. Check Engine Light illuminated on the dashboard

How to Fix P0656 GMC

  1. Diagnose the issue by using a diagnostic scanner to retrieve the trouble codes and perform a visual inspection of the fuel level sensor and its wiring.
  2. Test the fuel level sensor using a multimeter to check for proper resistance readings.
  3. Replace the fuel level sensor if it is found to be faulty, damaged, or corroded.
  4. Repair or replace any damaged wiring or connectors in the sensor circuit.
  5. Clear the trouble codes and test drive the vehicle to ensure that the issue has been resolved.

Cost to Fix P0656 GMC

The typical repair costs for a Fuel Level Output Circuit Malfunction can range from $150 to $300, depending on the extent of the repairs needed. This estimate includes the cost of a new fuel level sensor, any necessary wiring or connector replacements, and labor charges. It is important to note that specific diagnosis time and labor rates at auto repair shops can vary, so it is advisable to inquire with local shops for a more accurate estimate.

When is the Code Detected?

If the fault detection circuit senses a voltage other than what the PCM expects, the fault line status changes causing the P0656 code will set.

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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 P0656 GMC Code

No Frequently Asked Questions about P0656 GMC Code found.

Discuss the causes and fixes for P0656 GMC OBDII Code

  • una gran ayuda seria, indicar que piezas son las que se tienen que cambiar para solucionar el problema.

    a serious help, indicate that parts are those that have to be changed to solve the problem.

  • Gracias por su comentario, el problem es que cada modelo y año tienen las partes en diferentes locaciones y son muchas.
    Que modelo y año es su vehículo?