Air/Fuel Sensor: Tacoma

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2002 Toyota Tacoma, 2002 Toyota RAV4, 2002 Toyota Prius, 2002 Toyota MR2, and 2002 Toyota Highlander. 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 TESTING PROCEDURE under 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 5. Replace A/F sensor if resistance is not within specification. See A/F SENSOR HEATER RESISTANCE table. See AIR/FUEL SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.

A/F SENSOR HEATER RESISTANCE

Application & Temperature		Ohms
Camry
68°F (20°C)		1.8-3.4
932°F (500°C)		5.0-7.5
Camry Solara
68°F (20°C)		.8-1.4
Highlander
68°F (20°C)		1.8-3.4
932°F (500°C)		5.0-7.5
RAV4
68°F (20°C)		.8-1.4
1472°F (800°C)		1.8-3.2
Tacoma
68°F (20°C)		.8-1.4
1472°F (800°C)		1.8-3.2

Fig 1: Identifying Air/Fuel Sensor Electrical Connector Terminals (Camry)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: Testing Heater On Air/Fuel Sensor (Camry Solara)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 3: Identifying Air/Fuel Sensor Electrical Connector Terminals (Highlander)

Fig 4: Testing Heater On Air/Fuel Sensor (RAV4)

Fig 5: Testing Heater On Air/Fuel Sensor (Tacoma)