1994 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Sensor Operating Range Charts

CAMSHAFT SENSOR RESISTANCE

Application Ohms
Cold (1) 835-1400
(1) Sensor temperature of 14-122°F (-10-50°C).
COLD START INJECTOR RESISTANCE

Application Ohms
SC400 2-4
COLD START INJECTOR TIME SWITCH RESISTANCE

Terminals No. Temp. °F (°C) Ohms
1 (STA) & 2 (STJ) Less Than 59 (15) 25-45
1 (STA) & 2 (STJ) More Than 86 (30) 65-85
1 (STA) & Switch Body N/A 25-85
CRANKSHAFT SENSOR RESISTANCE

Application Ohms
Cold (1) 835-1400
Hot (2) 1060-1645
(1) Sensor temperature of 14-122°F (-10-50°C).
(2) Sensor temperature of 123-212°F (51-100°C).
ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

Temp. °F (°C) Ohms
-4° (-20) 10,000-20,000
32 (0) 4000-7000
68 (20) 2000-3000
104 (40) 900-1300
140 (60) 400-700
176 (80) 200-400
EGR GAS TEMPERATURE SENSOR RESISTANCE

Temp. °F (°C) Ohms
122 (50) 64,000-97,000
212 (100) 11,000-16,000
302 (150) 2000-4000
NOTE: Intake Air Temperature (IAT) sensor is part of volume airflow sensor.
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE (1)

Ambient Temp. °F (°C) Ohms
-4 (-20) 10,000-20,000
32 (0) 4000-7000
68 (20) 2000-3000
104 (40) 900-1300
140 (60) 400-700
(1) Measure resistance between terminals THA and E2 of VAF sensor.
IDLE AIR CONTROL (IAC) VALVE RESISTANCE (1)

Application Ohms
SC400 34-54
(1) Measure resistance between terminal B1 and terminals S1 and S3. Measure resistance between terminal B2 and terminals S2 and S4.
KNOCK SENSOR RESISTANCE (1)

Terminal Ohms
Terminal To Sensor Body Infinity (No Continuity)
(1) Replace sensor if continuity exists.
OXYGEN SENSOR HEATER RESISTANCE (1)

Application Ohms @ 68°F (20°C)
SC400 5.1-6.3
(1) Measure resistance between terminals +B and HT of oxygen sensor 4-pin connector. See Fig 1.
Fig 1: Measuring Oxygen Sensor Heater Resistance (SC400)
G93I78194Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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