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Sensor Range Charts

NOTE: Unless stated otherwise in test procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

Temperature Ohms
86°F (30°C) 1500-2000
176°F (80°C) 275-375
HEATED OXYGEN SENSOR (HO2S) RESISTANCE

Terminals No. Ohms
1 & 2 0.0-19.9
HEATED OXYGEN SENSOR (HO2S) VOLTAGE

Condition (1) Volts
Lean Approx. 0.2
Rich Approx. 0.7
(1) Measured between connector terminal and ground.
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE

Terminals Ohms
Measure Between Sensor Terminals Approx. 1600-2800
KNOCK SENSOR RESISTANCE

Terminal No. Ohms
1 & 2 Infinity
1 & 3 Infinity
2 & 3 Infinity