P1159 HONDA Possible Causes
- Faulty Air/Fuel Ratio Sensor 1
- Air/Fuel Ratio Sensor 1 harness is open or shorted
- Poor electrical connection in the Air/Fuel Ratio Sensor 1 circuit
How to Fix Code P1159 HONDA?
Start by checking the “Possible Causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
When is the Code Detected?
A malfunction is detected and the code is stored if the heater element is not activated or if the voltage at the Engine Control Module (ECM) terminals is a specified value or less for at least a defined period when power is supplied to the A/F sensor heater (sensor 1).
Possible Symptoms
- Check Engine Light On (or Service Engine Soon Warning Light)
P1159 HONDA Meaning
The Air/Fuel Ratio (A/F) Sensor 1 is installed in the exhaust system and detects the oxygen concentration in the exhaust gases. The A/F sensor sends the output voltage to the Engine Control Module (ECM). A heating element for the sensor element is built into the A/F sensor (sensor 1). It is activated and heats the sensor to stabilize and speed up the detection of oxygen concentration by controlling the current flowing through the heater. The current increase stabilizes when the voltage applied to the element electrode reaches a certain range because the amount of oxygen that passes through the diffusion layer is limited. The current amperage is proportional to the oxygen concentration in the exhaust gases, so the air/fuel ratio is detected by measuring the current amperage. The ECM compares a preset target air/fuel ratio with the detected air/fuel ratio and controls the fuel injection timing.
If the A/F sensor (sensor 1) voltage is low, the air/fuel ratio is lean and the ECM uses A/F feedback control to issue a Rich command. If the A/F sensor (sensor 1) voltage is high, the air/fuel ratio is rich and the ECM uses A/F feedback control to issue a Lean command.