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Engine Controls - Sensor Operating Range Charts: Introduction

Sensor operating range information can help determine if a sensor is out of calibration. An out-of-calibration sensor may not set a trouble code, but it may cause driveability problems.

NOTE: Unless stated otherwise in test procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
NOTE: For testing of sensors not listed, see appropriate Diagnostic Trouble Code (DTC) test in appropriate SELF-DIAGNOSTICS article and/or appropriate SYSTEM & COMPONENT TESTING article.
BRAKE LIGHT SWITCH

Pedal Position Ohms
Pressed
Measure Between Terminals No.
1 & 2 Infinity
3 & 4 Continuity
Released
Measure Between Terminals No.
1 & 2 Continuity
3 & 4 Infinity
ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE

Temperature Ohms
68°F (20°C) 2200-3000
86°F (30°C) 1500-2000
176°F (80°C) 275-375
212°F (100°C) 150-240
FUEL INJECTOR RESISTANCE

Application (1) Ohms
1.8L (2) 12-13
2.7L (2) 13.5-15.5
2.8L (2) 13.5-15.5
4.2L (2) 13-16
(1) Measured at room temperature.
(2) Add 4-6 ohms if fuel injector is at operating temperature.
HEATED OXYGEN SENSOR RESISTANCE

Application Ohms
1.8L, 2.7L & 2.8L
Measure Between Terminals No.
1 & 2 6.4-47.5
4.2L
Measure Between Terminals No.
1 & 2 0.0-0.9
HEATED OXYGEN SENSOR VOLTAGE

Condition Volts
Lean 0.0-0.3
Rich 0.7-1.0
INTAKE AIR TEMPERATURE SENSOR RESISTANCE

Temperature °F (°C) (1) K/Ohms
- 20 13.8
0 5.5
20 2.4
40 1.1
60 .6
(1) Resistance should decrease as temperature increases.
LEAK DETECTION PUMP

Terminals No. Ohms
1 & 3 640-720
2 & 3 17.5-27.5
VARIOUS SENSORS, SOLENOIDS & VALVES

Application Ohms
Camshaft Adjustment Solenoid 10-18
Charge Air Pressure Sensor 22-30
Engine Speed Sensor (1.8L, 2.7L & 2.8L)
1 & 2 Infinity
1 & 3 Infinity
2 & 3 730-1000
Engine Speed Sensor (4.2L)
1 & 2 Infinity
1 & 3 Infinity
2 & 3 450-1000
Evaporative Emissions Canister Purge Regulator Valve 22-30
Intake Manifold Change Over Valve 25-35
Knock Sensor
1 & 2 Infinity
1 & 3 Infinity
2 & 3 Infinity
Secondary Air Injection Solenoid 27-30
Turbocharger Recirculating Valve 27-30
Wastegate By-Pass Regulator Valve 25-35