Code 45 - Lambda sensor B - right bank
If one of these fault codes (#44 or #45) is displayed check the wiring to that particular lambda sensor. In addition this fault will be displayed if the vehicle has a condition which causes it to run very lean or very rich on one side (example - a vacuum leak or a bad injector). This code often appears in conjunction with the misfire codes in cases of bad ignition misfire (cross-firing plug wires)
If both codes are displayed, the voltage supply to the heater coils of the sensors must be checked. Check for 12V appearing on the O2 signal lead, and check the heater circuit for shorts.
(a lambda sensor is an O2 sensor)