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 signal that tells the car when to stop using alternative fuel, like electricity or natural gas. It's like when a light switch doesn't work properly, and the light won't turn on or off when you want it to.
The P25C1 code is set when the vehicle's computer detects an issue with the circuit responsible for disabling the alternative fuel system.
The P25C1 code indicates that the Powertrain Control Module (PCM) has detected a malfunction in the circuit that controls the disable signal for the alternative fuel system. This could be due to a wiring issue, a faulty sensor, or a problem with the PCM itself.
• Check Engine Light is on
• Vehicle may not switch to alternative fuel
• Reduced fuel efficiency
• Faulty wiring or connectors in the disable signal circuit
• Malfunctioning alternative fuel system sensor
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code
• Inspect wiring and connectors for damage
• Test the alternative fuel system sensor
• Repair or replace damaged wiring and connectors
• Replace faulty alternative fuel system sensor
• Reprogram or replace the PCM if necessary
• OBD-II scanner
• Multimeter
• Wire repair tools
$150 - $500
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly inspect and maintain electrical connections
• Ensure alternative fuel system components are serviced
• Follow manufacturer-recommended maintenance schedules
Sensor Issue
• Have the vehicle inspected by a professional
• Avoid using alternative fuel until the issue is resolved
Check if your vehicle's powertrain warranty covers this issue.
This code has been more prevalent in hybrid and alternative fuel vehicles as they age and their electrical systems experience wear.
Moderate – While the vehicle can still operate, it may not use alternative fuel efficiently, leading to higher costs.
Driving with this code may not be illegal, but it can lead to increased emissions and reduced fuel efficiency.
• Vehicle must be running
• Alternative fuel system must be engaged
The alternative fuel disable signal circuit is typically located near the PCM and the alternative fuel system components.
Q: Can I drive my car with the P25C1 code?
A: Yes, but it might not use alternative fuel efficiently, which could cost you more in fuel.
Q: Will the check engine light turn off after repairs?
A: Yes, once the issue is fixed and the code is cleared, the light should turn off.
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