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 that lets you choose how your car uses fuel. It's like when a light switch in your house doesn't work right.
The vehicle's computer has detected a low voltage or resistance issue in the circuit that controls the fuel mode select switch.
The P25A6 code indicates that the Powertrain Control Module (PCM) has detected a low voltage condition in the fuel mode select switch circuit. This switch allows the driver to select different fuel modes, such as economy or performance, and the low voltage suggests a problem with the circuit's integrity.
• Check Engine Light is on
• Inability to switch fuel modes
• Reduced fuel efficiency
• Faulty fuel mode select switch
• Damaged wiring or connectors in the circuit
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Inspect the fuel mode select switch for damage.
• Check wiring and connectors for corrosion or damage.
• Test the circuit for proper voltage and resistance.
• Replace the faulty fuel mode select switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Screwdriver set
$100 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect electrical connections.
• Avoid exposure to moisture and corrosive elements.
• Perform routine maintenance checks.
Sensor Issue
• Avoid switching fuel modes until the issue is fixed.
• Consult a professional mechanic for accurate diagnosis.
Check with the vehicle manufacturer for warranty coverage on electrical components.
This code has been associated with vehicles that have selectable fuel modes, often appearing in models with advanced fuel management systems.
Moderate – It is advisable to address this issue soon to maintain optimal vehicle performance and fuel efficiency.
Driving with a malfunctioning fuel mode switch may affect vehicle performance and emissions compliance.
• Vehicle at operating temperature
• Fuel mode switch engaged
The fuel mode select switch is typically located on the dashboard or center console.
Q: Can I drive my car with the P25A6 code?
A: Yes, but it is recommended to fix the issue soon to avoid potential fuel efficiency problems.
Q: Will the P25A6 code affect my fuel economy?
A: Yes, it may cause reduced fuel efficiency if the vehicle is stuck in an undesired fuel mode.
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