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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.

CAUTION: DO NOT use ECM ground terminals when measuring voltage.
NOTE: For sensors not listed, see appropriate DTC test in appropriate SELF-DIAGNOSTICS article.
NOTE: Unless stated otherwise in test procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
ACCELERATOR PEDAL POSITION SENSOR VOLTAGE (FX35 & FX45)

Application Volts
APP Sensor No. 1 (1)
Fully Released 0.5-1.0
Fully Depressed 3.9-4.8
APP Sensor No. 2 (2)
Fully Released 0.15-0.60
Fully Depressed 1.95-2.4
(1) Measured between ground and ECM terminal No. 106 by backprobing.
(2) Measured between ground and ECM terminal 98 by backprobing.
ACCELERATOR PEDAL POSITION SENSOR VOLTAGE (G35 & I35)

Application Volts
APP Sensor No. 1 (1)
Fully Released 0.41-0.72
Fully Depressed More Than 3.2
APP Sensor No. 2 (2)
Fully Released 0.07-0.49
Fully Depressed More Than 1.49
(1) Measured between ground and ECM terminal No. 73 by backprobing.
(2) Measured between ground and ECM terminal 74 by backprobing.
ACCELERATOR PEDAL POSITION SENSOR VOLTAGE (Q45)

Application Volts
APP Sensor No. 1 (1)
Fully Released More Than .36
Fully Depressed Less Than 4.75
APP Sensor No. 2 (2)
Fully Released More Than .18
Fully Depressed Less Than 2.37
(1) Measured between ground and ECM terminal No. 87 by backprobing.
(2) Measured between ground and ECM terminal No. 117 by backprobing.
CRANKSHAFT POSITION SENSOR RESISTANCE (FX35, FX45 & M45)

Terminal (Polarity) Ohms @ 77°F (25°C)
1 (+)-2 (-) Except Zero Or Infinity
1 (+)-3 (-) Except Zero Or Infinity
2 (+)-3 (-) Except Zero Or Infinity
CRANKSHAFT POSITION SENSOR RESISTANCE (G35, I35, QX4 & Q45)

Application Ohms @ 68°F (20°C)
G35, I35 & Q45 (1)
QX4 470-570
(1) Resistance specification is not available from manufacturer.
ENGINE COOLANT TEMPERATURE SENSOR SPECIFICATIONS

Temperature °F (°C) Volts (1) Resistance Ohms
14 (-10) 4.4 7000-11,400
68 (20) 3.5 2100-2900
122 (50) 2.2 680-1000
194 (90) 1.0 236-260
(1) Measured between ground and ECM terminal No. 73 (FX35 & FX45), No. 93 (on G35 & I35), No. 121 (on M45 & Q45), or No. 70 (on QX4) by backprobing.
FUEL TANK TEMPERATURE SENSOR SPECIFICATIONS

Temperature °F (°C) Volts (1) Resistance Ohms
68 (20) 3.5 2300-2700
122 (50) 2.2 790-900
(1) Measured between ground and ECM terminal No. 107 (on FX35 & FX45), No. 75 (on G35 & I35) or No. 92 (on M45, Q45 & QX4) by backprobing.
HEATED OXYGEN SENSOR VOLTAGE (1)

Condition Volts
Lean 0-0.3
Rich 0.6-1.0
(1) Reading displayed on an OBD-II scan tool. For complete HO2S sensor testing, see appropriate test under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.
INTAKE AIR TEMPERATURE SENSOR SPECIFICATIONS

Temperature °F (°C) Volts (1) Resistance (K/Ohms)
FX35, FX45, G35 & I35
77 (25) 3.32 1.9-2.1
176 (80) 1.23 310-370
QX4
68 (20) 3.50 2.1-2.9
176 (80) 1.23 270-380
M45 & Q45
14 (-10) 4.43 7.9-9.3
77 (25) 3.32 1.9-2.1
176 (80) 1.23 0.31-0.37
(1) Measured between ground and ECM terminal No. 34 (on FX35 & FX45), No. 66 (on I35 & G35), No. 99 (on M45 & Q45) or No. 64 (on QX4) by backprobing.
MASS AIRFLOW SENSOR VOLTAGE SPECIFICATIONS (1)

Application Volts
FX35 & FX45
Key On, Engine Off (2) About 0.4
Idle (2) 1.1-1.5
2500 RPM (2) 1.7-2.4
4000 RPM (2) 1.1-1.5 to About 4.0
G35, I35, M45 & Q45
Key On, Engine Off (2) About 1.0
Idle (2) 1.1-1.5
2500 RPM (2) 1.7-2.4
4000 RPM (2) 1.1-1.5 to About 4.0
QX4
Key On, Engine Off (3) About 1.0
Idle (3) 1.2-1.8
2500 RPM (3) 1.6-2.2
4000 RPM (3) 1.2-1.8 to About 4.0
(1) With engine at normal operating temperature.
(2) Measured between ground and ECM terminal No. 51 (On FX35 & FX45), No. 62 (on G35 & I35) & No. 91 (on Q45) by backprobing.
(3) Measured between ground and ECM terminal No. 61 (on QX4) by backprobing.
RADIATOR COOLANT TEMPERATURE SENSOR SPECIFICATIONS (Q45)

Temperature °F (°C) Volts (1) Resistance (K/Ohms)
14 (-10) 4.4 9.017-9.723
68 (20) 3.5 2.437-2.595
194 (90) 0.9 2416-2575
230 (110) 0.64 .1451-.1522
302 (150) 0.32 .0593-.0627
(1) Measured between ground and ECM terminal 122 by backprobing.
THROTTLE POSITION SENSOR VOLTAGE (FX35 & FX45)

Application Volts
TP Sensor No. 1 (1)
Fully Released More Than .36
Fully Depressed Less Than 4.75
TP Sensor No. 2 (2)
Fully Released Less Than 4.75
Fully Depressed More Than .36
(1) Measured between ground and ECM terminal No. 50 by backprobing.
(2) Measured between ground and ECM terminal No. 69 by backprobing.
THROTTLE POSITION SENSOR VOLTAGE (M45 & Q45)

Application Volts
TP Sensor No. 1 (1)
Fully Released More Than .36
Fully Depressed Less Than 4.75
TP Sensor No. 2 (2)
Fully Released Less Than 4.75
Fully Depressed More Than .36
(1) Measured between ground and ECM terminal No. 108 by backprobing.
(2) Measured between ground and ECM terminal No. 98 by backprobing.
THROTTLE POSITION SENSOR VOLTAGE (QX4)

Application (1) Volts
Fully Released 0.15-0.85
Fully Depressed 3.5-4.7
(1) Measured between ground and ECM terminal No. 91 by backprobing.
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