Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble with the signal that tells it to stop using an alternative fuel, like electricity or natural gas. It's like when a remote control can't tell the TV to turn off.
The P25C3 code indicates that there is a low voltage signal in the circuit responsible for disabling the use of alternative fuel in the vehicle.
The P25C3 code is triggered when the vehicle's powertrain control module (PCM) detects a low voltage condition in the circuit that manages the disable signal for alternative fuel usage. This could be due to a wiring issue, a faulty sensor, or a malfunctioning PCM.
• Check engine light illuminated
• Vehicle may not switch to alternative fuel mode
• Reduced fuel efficiency
• Faulty alternative fuel disable switch
• Damaged wiring or connectors in the circuit
• Malfunctioning powertrain control module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connectors related to the alternative fuel disable circuit.
• Test the alternative fuel disable switch for proper operation.
• Repair or replace any damaged wiring or connectors.
• Replace the faulty alternative fuel disable switch.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdrivers
$100 - $500
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regular inspection of wiring and connectors
• Routine maintenance of the fuel system
• Timely software updates for the PCM
Sensor Issue
• Avoid driving in alternative fuel mode until the issue is resolved.
• Schedule a diagnostic check with a professional mechanic.
Check with the vehicle manufacturer for warranty coverage on PCM and related components.
This code has been more common in hybrid and alternative fuel vehicles as they rely on complex electronic systems.
Moderate – It is recommended to address this issue soon to ensure proper vehicle operation.
Driving with this code may not comply with emissions regulations and could affect vehicle safety.
• Vehicle in 'On' position
• Alternative fuel mode engaged
The alternative fuel disable switch is typically located near the fuel system or integrated into the vehicle's control module.
Q: Can I drive my car with the P25C3 code?
A: It's possible, but not recommended as it may affect fuel efficiency and vehicle performance.
Q: Will the check engine light go off after fixing the issue?
A: Yes, once the issue is resolved and the code is cleared, the check engine light should turn off.
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