P00B3 — Radiator Coolant Temperature Sensor Circuit Low

What Does P00B3 Mean?

P00B3 is a diagnostic trouble code indicating: Radiator Coolant Temperature Sensor Circuit Low. This code relates to the fuel and air metering system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P00B3

⚠️ Check Engine Light (MIL) illuminated
⚠️ Radiator Coolant Temperature Sensor reading at zero or minimum value
⚠️ Related system not functioning or in fail-safe mode
⚠️ Poor fuel economy

Common Causes

🔍 Open or broken wire in Radiator Coolant Temperature Sensor circuit
🔍 Poor ground connection at Radiator Coolant Temperature Sensor
🔍 Faulty Radiator Coolant Temperature Sensor with no output signal
🔍 Disconnected or loose Radiator Coolant Temperature Sensor connector
🔍 Blown fuse in related circuit

Frequently Asked Questions

What does P00B3 mean?

P00B3 indicates: Radiator Coolant Temperature Sensor Circuit Low. The vehicle's computer has detected that the Radiator Coolant Temperature Sensor is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P00B3?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P00B3 for extended periods may cause additional problems.

How much does it cost to fix P00B3?

Repair costs for P00B3 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 Radiator Coolant Temperature Sensor circuit
🔧 Clean and secure Radiator Coolant Temperature Sensor connector and ground points
🔧 Replace failed Radiator Coolant Temperature Sensor

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.

P00B3: Radiator Coolant Temperature Sensor Circuit Low