Possible causes

– Faulty Oxygen Air/Fuel Sensor Bank 1 Sensor 1
– Oxygen Air/Fuel Sensor Bank 1 Sensor 1 harness is open or shorted
– Oxygen Air/Fuel Sensor Bank 1 Sensor 1 circuit poor electrical connection
– Faulty EFI Relay
– Faulty Injector
– Faulty Engine Control Module (ECM)

When is the code detected?

P2195 indicate a malfunction related to bank 1 of the A/F sensor circuit.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Excessive Fuel Consumption

P2195 LEXUS Description

The Air-Fuel ratio (A/F) sensor provides output voltage approximately equal to the existing air-fuel ratio.
The A/F sensor output voltage is used to provide feedback for the Engine Control Module (ECM) to control the air-fuel ratio.
With the A/F sensor output, the ECM can determine deviation from the stoichiometric air-fuel ratio and control proper injection time. If the A/F sensor is malfunctioning, the ECM is unable to accurately control air-fuel ratio.
The A/F sensor is equipped with a heater which heats the zirconia element. The heater is also controlled by the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), current flows to the heater which heats the sensor to facilitate detection of accurate oxygen concentration.
The A/F sensor is a planar type. Compared to a conventional type, the sensor and heater portions are narrower. Because the heat of the heater is conducted through the alumina to zirconia (of the sensor portion), sensor activation is accelerated.

LEXUS Technical Service Bulletins for P2195 code