P05F1 — Reductant Pump Supply Voltage Circuit Stuck On

What Does P05F1 Mean?

P05F1 is a diagnostic trouble code indicating: Reductant Pump Supply Voltage Circuit Stuck On. This code relates to the vehicle speed and idle control system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P05F1

⚠️ Check Engine Light (MIL) illuminated
⚠️ Reductant Pump Supply Voltage remains active when it should be off
⚠️ Related system running continuously
⚠️ Erratic idle speed

Common Causes

🔍 Reductant Pump Supply Voltage mechanically stuck in active position
🔍 Short circuit holding Reductant Pump Supply Voltage control on
🔍 Faulty Reductant Pump Supply Voltage driver circuit in ECM/PCM

Frequently Asked Questions

What does P05F1 mean?

P05F1 indicates: Reductant Pump Supply Voltage Circuit Stuck On. The vehicle's computer has detected that the Reductant Pump Supply Voltage is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P05F1?

Only short distances if absolutely necessary. P05F1 affects a critical system and should be diagnosed within a few days to avoid further damage.

How much does it cost to fix P05F1?

Repair costs for P05F1 typically range from $50 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 Reductant Pump Supply Voltage for mechanical binding or debris
🔧 Replace stuck Reductant Pump Supply Voltage
🔧 Check Reductant Pump Supply Voltage control circuit for short

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
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.

P05F1: Reductant Pump Supply Voltage Circuit Stuck On