Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the switch in your car that lets you choose between different fuel modes, like switching from regular to eco mode.
The P25A4 code is triggered when the Engine Control Module (ECM) detects an issue with the circuit that controls the fuel mode selection switch.
The Fuel Mode Select Switch Circuit is responsible for allowing the driver to choose different fuel modes, such as economy or performance modes. This circuit sends signals to the ECM to adjust fuel delivery and engine parameters accordingly. A malfunction in this circuit can prevent the vehicle from switching modes or cause incorrect mode selection.
• Inability to switch fuel modes
• Check engine light illuminated
• Unexpected changes in fuel efficiency
• Faulty fuel mode select switch
• Damaged wiring or connectors in the circuit
• Malfunctioning ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Verify the presence of the P25A4 code using an OBD-II scanner.
• Inspect the fuel mode select switch for physical damage.
• Check the wiring and connectors for signs of wear or damage.
• Replace the faulty fuel mode select switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regular maintenance checks on electrical systems
• Avoid exposure of connectors to moisture
• Use fuel modes as recommended by the manufacturer
Sensor Issue
• Avoid switching fuel modes until the issue is resolved.
• Consult a professional mechanic if unsure about repairs.
Check with your vehicle manufacturer; some components may be covered under warranty.
This code has been more prevalent in vehicles with advanced fuel management systems introduced in the last decade.
Moderate – While the vehicle may still operate, fuel efficiency and performance could be affected.
Driving with a malfunctioning fuel mode switch may not be illegal, but it can lead to increased emissions and reduced fuel efficiency.
• Vehicle in park with engine running
• Attempt to switch fuel modes
The fuel mode select switch is typically located on the dashboard or near the gear shifter.
Q: Can I drive my car with the P25A4 code?
A: Yes, but you may experience reduced fuel efficiency and performance.
Q: How do I reset the check engine light after fixing the issue?
A: Use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes.
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