P256E Fault Code

Engine Idle Speed Selector Sensor/Switch Circuit Intermittent/Erratic

• What does that mean?
• Symptoms
• Causes
• Solutions

The P256E fault code indicates an issue with the engine idle speed selector sensor or switch circuit. This code is triggered when the vehicle's engine control module (ECM) detects intermittent or erratic signals from the idle speed sensor. The idle speed selector is essential for maintaining stable engine RPM, allowing for smooth operation at idle.

What are the symptoms of the P256E code?

Symptoms associated with the P256E code can vary but may include:

• Unstable or fluctuating engine idle speed
• Stalling or rough idle when coming to a stop
• Increased fuel consumption due to erratic idle behavior
• Check Engine Light (CEL) illumination on the dashboard

What causes the P256E code?

Common causes of the P256E code may include:

• Faulty idle speed selector sensor
• Damaged wiring or connectors in the sensor circuit
• A malfunctioning engine control module (ECM)
• Mechanical issues in the throttle body or idle air control valve
• Poor electrical connections due to corrosion or wear

How to fix P256E?

To resolve the P256E fault code, follow these steps:

• Inspect the wiring and connectors related to the idle speed sensor for any signs of damage or corrosion.
• Test the idle speed selector sensor for proper operation; replace it if necessary.
• Check the throttle body and idle air control valve for cleanliness and functionality.
• Clear the fault code from the ECM and test drive the vehicle to see if the issue reoccurs. If the code returns, further diagnostic testing may be necessary.