2003 Toyota RAV4 P1155 Fault Code: Diagnosis and Repair Guide
My 2003 Toyota RAV4 with a 4-cylinder automatic transmission and 90,000 miles has been displaying fault code P1155. What is the correct diagnosis and fix? Thanks for any insights.
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P1155
Comments (4)
Anonymous
2007-08-07 22:31
I want to sincerely thank everyone for this helpful thread — it saved me a lot of time and money. The issue was indeed the air/fuel ratio sensor on Bank 2, which resolved the P1155 code after replacement. This repair cost me around $300 total (parts and labor). Thanks again for the clear explanation!
Anonymous
2007-08-08 11:19
You're very welcome — glad this information helped you resolve your issue. If others have similar problems, feel free to ask more questions.
Anonymous
2008-05-24 19:22
Hi there, I'm experiencing the same P1155 code on my 2003 Toyota RAV4. How much did it cost you for diagnosis and repair? Any tips on where to find a reliable replacement sensor or mechanic?
Fault code P1155 refers to the 'Bank 2 Sensor 1 Air/Fuel Ratio Sensor Heater Circuit'. This component is not an oxygen (O2) sensor but operates in a similar location within the exhaust stream. The Powertrain Control Module (PCM) detects either excessive or no current flow through the heater circuit, indicating potential failure. While a faulty air/fuel ratio sensor is the most common cause, damaged wiring, open or shorted power/ground circuits should also be ruled out before replacement.