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Engine Controls - Sensor Range Charts: Introduction

Sensor operating range information can help determine if a sensor is out of calibration. Although an out-of-calibration sensor may not set a trouble code, 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-megaohm input impedance.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR TEST

Temperature - °F (°C) (1) Volts
Accord & Odyssey
-4 (-20) 5.0
176-200 (80-93) 0.4-0.7
302 (150) 0.0
(2)Ohms 
Civic, CR-V & Prelude
32 (0) 5000
104 (40) 1000
140 (60) 500
(1) Measure voltage at appropriate PCM terminals. See WIRING DIAGRAMS article.
(2) Measure resistance across sensor terminals.
EXHAUST GAS RECIRCULATION (EGR) VALVE LIFT SENSOR VOLTAGE TEST

Position (1) Volts (Approximate)
All Models
Idle 1.2
8 In. Hg (27 kPa) 4.3
(1) Measure voltage at appropriate PCM terminals. See WIRING DIAGRAMS article. Voltage should increase smoothly as vacuum is applied.
FUEL TANK PRESSURE SENSOR

Vacuum Applied - In. Hg Volts
All Models
-2 .5
0 2.5
2 4.5
INTAKE AIR TEMPERATURE (IAT) SENSOR TEST

Temperature - °F (°C) (1) Volts
Accord & Odyssey
-4 (-20) 5.0
302 (150) 0.0
(2)Ohms 
Civic, CR-V & Prelude
32 (0) 5000
104 (40) 1000
176 (80) 500
(1) Measure voltage at appropriate PCM terminals. See WIRING DIAGRAMS article.
(2) Measure resistance across sensor terminals.
MAP SENSOR VOLTAGE TEST

Vacuum Applied - In. Hg (1) Volts
Accord & Odyssey
0 0.0
30 5.0
Civic, CR-V & Prelude
5 2.5
10 2.0
15 1.5
20 1.0
25 0.5
(1) Measure voltage at appropriate PCM terminals. See WIRING DIAGRAMS article.
OXYGEN SENSOR VOLTAGE TEST

Condition (1) Volts
Lean Less Than 0.4
Rich Greater Than 0.6
(1) Measure voltage between ground and oxygen sensor terminal using a high-impedance DVOM.
THROTTLE POSITION (TP) SENSOR

Condition Volts/Value
Throttle Valve
Fully Closed
Accord & Odyssey (1) 10%
Civic, CR-V & Prelude (2) 0.5
Wide Open
Accord & Odyssey (1) 90%
Civic, CR-V & Prelude (2) 4.5
(1) Check throttle position with scan tool.
(2) Backprobe terminals at PCM.
VEHICLE SPEED SENSOR (VSS) TEST

Application (1) Volts
All Models (2)
(1) Backprobe terminals at PCM.
(2) Voltage will fluctuate between zero and 5 volts while rotating drive wheel.