P25C2 — Alternative Fuel Disable Signal Circuit High

What Does P25C2 Mean?

P25C2 is a diagnostic trouble code indicating: Alternative Fuel Disable Signal Circuit High. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P25C2

⚠️ Check Engine Light (MIL) illuminated
⚠️ Alternative Fuel Disable Signal reading stuck at maximum value
⚠️ Related system operating erratically or in default mode
⚠️ Reduced engine performance

Common Causes

🔍 Short to voltage in Alternative Fuel Disable Signal wiring harness
🔍 Corroded or water-damaged Alternative Fuel Disable Signal connector
🔍 Faulty Alternative Fuel Disable Signal outputting maximum voltage
🔍 Damaged wiring rubbing against metal components
🔍 ECM/PCM internal fault (rare)

Frequently Asked Questions

What does P25C2 mean?

P25C2 indicates: Alternative Fuel Disable Signal Circuit High. The vehicle's computer has detected that the Alternative Fuel Disable Signal is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P25C2?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P25C2 for extended periods may cause additional problems.

How much does it cost to fix P25C2?

Repair costs for P25C2 typically range from $20 to $300, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect and repair Alternative Fuel Disable Signal wiring for short to voltage
🔧 Clean or replace corroded Alternative Fuel Disable Signal connector
🔧 Replace faulty Alternative Fuel Disable Signal

1
Find your vehicle above
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2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P25C2: Alternative Fuel Disable Signal Circuit High