P0051

Symptoms

• Increased fuel consumption
• Unstable engine idling
• Reduced engine power
• Check Engine Light Illuminates
• Dips during acceleration
• Increased toxicity of exhaust gases

Causes

• Faulty oxygen sensor heater
• Open circuit in the heater circuit wiring
• Short circuit to ground
• Oxidation or corrosion of connectors
• Faulty heater circuit fuse
• Problems with the engine ECU
• Poor contact in the sensor connector

How to Fix

1. Connect the diagnostic scanner and read the error codes
2. Check the supply voltage at the oxygen sensor connector
3. Measure the resistance of the sensor heater (usually 2-14 Ohms)
4. Check the integrity of the wiring from the ECU to the sensor
5. Inspect connectors for oxidation and corrosion
6. Check heater circuit fuses
7. If necessary, replace the oxygen sensor
8. Clear error codes and test drive

Related codes

Error P0051 by Vehicle Brand