P1051 Citroen Air Fuel Ratio Sensor 1 Heater Control Circuit Low Bank 2

Possible causes

– Air Fuel Ratio Sensor 1 Bank 2 harness is open or shorted
– Air Fuel Ratio Sensor 1 Bank 2 circuit poor electrical connection
– Faulty Air Fuel Ratio Sensor 1 Bank 2

Tech description

What about the obd code?

The current amperage in the heated air fuel ratio (A/F) sensor 1 heater circuit is out of the normal range. An excessively low voltage signal is sent to Engine Control Module (ECM) through the heated air fuel ratio (A/F) sensor 1 heater.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1051 Citroen Description

The Engine Control Module (ECM) performs ON/OFF duty control of the Air Fuel Ratio (A/F) sensor 1 heater corresponding to the engine operating condition to keep the temperature of A/F sensor 1 element at the specified range.