What causes P1159 on a Honda?

Aging air/fuel ratio sensor 1 with a failing high-side terminal Corroded or moisture-damaged A/F sensor 1 connector Chafed high-side signal wire shorted to ground Exhaust leak skewing the sensor reading low Failing ECM sensor driver circuit

How do I fix P1159 on a Honda?

Read live A/F sensor data with a Honda HDS scan tool and note the stuck-low terminal Inspect the sensor connector for green corrosion and pin damage Test the high-side wire for shorts to ground with a multimeter Smoke test the exhaust ahead of the sensor for dilution leaks Replace air/fuel ratio sensor 1 after proving the wiring and reference voltage good

P1159 Air/Fuel Ratio Sensor 1 High Terminal Low Voltage

Q: What does P1159 mean on a Honda?

P1159. Air/Fuel Ratio Sensor 1 High Terminal Low Voltage. Applies to Civic, Accord, CR-V with wideband A/F sensors.

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Civic, Accord, CR-V with wideband A/F sensors

What does P1159 mean on a Honda?

P1159. Air/Fuel Ratio Sensor 1 High Terminal Low Voltage. This Honda-enhanced code applies to Civic, Accord, CR-V with wideband A/F sensors.

Common causes of P1159

Aging air/fuel ratio sensor 1 with a failing high-side terminal
Corroded or moisture-damaged A/F sensor 1 connector
Chafed high-side signal wire shorted to ground
Exhaust leak skewing the sensor reading low
Failing ECM sensor driver circuit

How to fix P1159

Read live A/F sensor data with a Honda HDS scan tool and note the stuck-low terminal
Inspect the sensor connector for green corrosion and pin damage
Test the high-side wire for shorts to ground with a multimeter
Smoke test the exhaust ahead of the sensor for dilution leaks
Replace air/fuel ratio sensor 1 after proving the wiring and reference voltage good

Sources and review

Last updated 2026-09-07.