Air/Fuel Ratio Sensor: Tacoma
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 2003 Toyota Tacoma, 2003 Toyota RAV4, 2003 Toyota Prius, 2003 Toyota Matrix, and 2003 Toyota MR2. However, it is still accessible from the selected car via links, so may be relevant.
- Heated A/F sensor is mounted on exhaust pipe in front of catalytic converter. If problem exists in A/F sensor, heater or wiring circuit, a Diagnostic Trouble Code (DTC) may be stored in Engine Control Module (ECM). See SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs.
- To test heater resistance on A/F sensor, disconnect electrical connector for A/F sensor. Using ohmmeter, check resistance between +B and HT terminals on electrical connector. See Fig 1. Replace A/F sensor if resistance is not within specification. See A/F SENSOR HEATER RESISTANCE (TACOMA) table. See AIR/FUEL SENSOR
under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION - 4-CYLINDER article.A/F SENSOR HEATER RESISTANCE (TACOMA)
Application & Temperature Ohms 68°F (20°C) .8-1.4 1472°F (800°C) 1.8-3.2