P1231 — Fuel Pump Secondary Circuit Low, High Speed

What Does P1231 Mean?

P1231 is a manufacturer-specific diagnostic trouble code: Fuel Pump Secondary Circuit Low, High Speed. This code applies to OTHER, VOLKSWAGEN, BUICK, CADILLAC, CHEVY vehicles. Unlike generic OBD-II codes, manufacturer-specific codes are defined by the vehicle maker and may only apply to certain makes and models.

Symptoms of P1231

⚠️ Check Engine Light (MIL) illuminated
⚠️ Fuel Pump Secondary reading at zero or minimum value
⚠️ Related system not functioning or in fail-safe mode
⚠️ Reduced engine performance

Common Causes

🔍 Open or broken wire in Fuel Pump Secondary circuit
🔍 Poor ground connection at Fuel Pump Secondary
🔍 Faulty Fuel Pump Secondary with no output signal
🔍 Disconnected or loose Fuel Pump Secondary connector
🔍 Blown fuse in related circuit

Frequently Asked Questions

What does P1231 mean?

P1231 indicates: Fuel Pump Secondary Circuit Low, High Speed. The vehicle's computer has detected that the Fuel Pump Secondary is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1231?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1231 for extended periods may cause additional problems.

How much does it cost to fix P1231?

Repair costs for P1231 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

🔧 Repair broken wire or restore ground in Fuel Pump Secondary circuit
🔧 Clean and secure Fuel Pump Secondary connector and ground points
🔧 Replace failed Fuel Pump Secondary

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.

P1231: Fuel Pump Secondary Circuit Low, High Speed