Engine-Codes - Toyota - P0159 2011 TOYOTA CAMRY

P0159 2011 TOYOTA CAMRY - Oxygen Sensor Circuit Slow Response Bank 2 Sensor 2

Repair Importance Level: 2/3
Repair Difficulty Level: 2/3  What is this?
Table of contents

P0159 2011 TOYOTA CAMRY Possible Causes

  • Faulty Rear Heated Oxygen Sensor Bank 2
  • EFI Relay
  • Rear Heated Oxygen Sensor Bank 2 harness is open or shorted
  • Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection
  • Inappropriate fuel pressure
  • Faulty fuel injectors
  • Intake air leaks may be faulty
  • Exhaust gas leaks

How is the P0159 2011 TOYOTA CAMRY code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Tech Notes

Replacing the O2 Sensor 2 usually takes care of the problem

What is the cost to diagnose the P0159 2011 TOYOTA CAMRY code

Labor: 1.0

The cost to diagnose the P0159 2011 TOYOTA CAMRY code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
How much do you know about cars?

Take the AutoCodes.com automotive tests and turbo-charge your car repair knowledge

Play Now

When is the code detected?

The P0159 code is set when the Engine Control Module (ECM) detects that the rear O2 sensor takes more time to respond between rich and lean than the specified time.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • High Fuel Consumption
  • Excessive Smoke from Exhaust

P0159 2011 TOYOTA CAMRY Meaning

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric air-fuel level. For the purpose of helping the ECM to deliver accurate air-fuel ratio control, a Heated Oxygen (HO2) sensor is used.
The HO2 sensor is located behind the TWC, and detects the oxygen concentration in the exhaust gas. Since the sensor is integrated with the heater that heats the sensing portion, it is possible to detect the oxygen concentration even when the intake air volume is low (the exhaust gas temperature is low). When the air-fuel ratio becomes lean, the oxygen concentration in the exhaust gas is rich. The HO2 sensor informs the ECM that the post-TWC air-fuel ratio is lean (low voltage, i.e. less than 0.45 V). Conversely, when the air-fuel ratio is richer than the stoichiometric air-fuel level, the oxygen concentration in the exhaust gas becomes lean. The HO2 sensor informs the ECM that the post-TWC air-fuel ratio is rich (high voltage, i.e. more than 0.45 V). The HO2 sensor has the property of changing its output voltage drastically when the air-fuel ratio is close to the stoichiometric level.
The ECM uses the supplementary information from the HO2 sensor to determine whether the air-fuel ratio after the TWC is rich or lean, and adjusts the fuel injection time accordingly. Thus, if the HO2 sensor is working improperly due to internal malfunctions, the ECM is unable to compensate for deviations in the primary air-fuel ratio control.

More Information

Need more information on how to fix the P0159 2011 TOYOTA CAMRY code?
Get Access to Factory Service Manuals

Need more help?

Get the P0159 2011 Toyota Camry code diagnosed by a professional: Find a repair shop in your area