Check engine light on, code P1135

Engine Mechanical problem
2001 Toyota Camry 4 cyl Front Wheel Drive Automatic 110K miles

2001 Toyota Camry 2.2L Automatic engine light came on. Actron CP9180 AutoScanner indicates P1135, 1 of 1, Mod $10, Manufacturer Specific DTC, see service manual. Cleared code [unintentionally] and engine light came back on a day later. I have not yet verified that the code is the same. How do I find out what is wrong? Is a manual available?

I have read these two related 2carpros.com forum postings.
http://www.2carpros.com/forum/2001-camry-p1135-code-vt19838.html
http://www.2carpros.com/forum/2001-toyota-avalon-p1135-error-code-vt150375.html
The second post indicates, “Heated Oxygen Sensor (HO2S) is faulty on bank 1." Ok, are there any diagrams or test steps available that would help confirm the problem? Or is it already clear that a specific part needs to be replaced?

Thanks for any help!
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Update-1: I have verified that after the check engine light came back on, the code is indeed still P1135. I borrowed the Chiltons Import Auto Service Manual 2001 from my local library and now the challenge is to find information in this huge document!


While I have not yet found the Heated Oxygen Sensor (HO2S)", there is a section on OXYGEN (O2) SENSORS, with a sub-section on HEATING CIRCUIT TEST. Believing that a little bit of knowledge can be dangerous, for now I have only tried to identify the location of the sensors that may be involved in the reported P1135 code. The pictures provided are what I believe to be the sensors. I also disconnected the far end of one of the senor wires and found 4 pins inside the connector. Since I may be looking at the wrong parts, I'll continue looking for information, and hope some help will come in response to this post. Some good advice can help get this fixed without causing any more problems, and that is why I am posting!

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Update-2: The Chilton’s manual section on OXYGEN (O2) SENSORS has a sub-section labeled 4-WIRE SENSOR. The instructions indicated that I should disconnect the sensor pigtail from the vehicle harness and probe the harness to identify HPWR. With the car key turned on but the without the engine running, I measured and found 12.6V between only one of the four harness terminals and vehicle ground. Per the manual, those 12 volts identify the HPWR terminal on the harness, and the corresponding location on the sensor pigtail is also HPWR. The car key was turned off and removed from the car. I switched my multi-meter to measure resistance (ohms) and attached one of the leads to the HPWR on the pigtail. Using the other probe, I checked the remaining 3 terminals on the pigtail for continuity. The manual indicates that continuity should only be found on one of the remaining 3 pigtail terminals, and that would be the HGND terminal. However, I did not find any continuity. The manual indicates, “If no continuity was evident, or if continuity was evident from all unidentified terminals, the O2S sensor is defective." I take it that the O2S and HO2S are the same sensor.

The earlier postings/threads referenced above tell me the P1135 code indicates, “Heated Oxygen Sensor (HO2S) is faulty on bank 1." And the Chiltons manual leads to the same conclusion. So now that I believe my HO2S sensor is defective. It would help to hear a mechanic confirm this or otherwise tell me what I should be considering. If it is the HO2S sensor, how does one replace that? Are any particular tools appropriate? I’ll be looking for help in the manual.

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Update-3: What part do I need to replace my defective "Heated Oxygen Sensor (HO2S)"? Note: My 2001 Camry 2.2: Automatic is a California model. The stickers under the hood confirm that my engine model is 5SFE.


Engine: L4 (2.2L)
ID: 5SFE 234-9010 Gas Engine; Calif.; Calif.; DENSO is the O.E. Manufacturer / Air Fuel Ratio Sensor N/A Front
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