How to Fix Code P1155 2002 TOYOTA CAMRY?

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?

P1155 is set when the Engine Control Module (ECM) detects a malfunction in the heated oxygen sensor heater circuit.

Possible Symptoms

• Check Engine Light on (or Engine Warning Light soon to come on)

P1155 2002 TOYOTA CAMRY Meaning

The Air/Fuel Ratio (A/F) sensor must reach a minimum operating temperature of 1200 degrees F to produce an accurate voltage signal. The faster the Air/Fuel Ratio sensor reaches this temperature, the sooner the sensor will start sending an accurate signal to the Engine Control Module (ECM).
To achieve the required temperature, a heating element is included inside the Air/Fuel Ratio sensor. The ECM controls the Air/Fuel Ratio sensor heating element based on signals from engine coolant temperature and engine load. The ECM controls the heater circuit by allowing current to flow to ground.
The ECM monitors the voltage signal received through the heater circuit and determines the circuit’s status by comparing the detected voltage to factory specifications.