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Engine Controls - Sensor 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 will cause driveability problems.

NOTE: Unless stated otherwise in test procedure, perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
ECT (1), DFT (2) & IAT (3) SENSOR RESISTANCE (4)

°F (°C) Ohms
212 (100) 177
194 (90) 241
176 (80) 332
158 (70) 467
140 (60) 667
122 (50) 973
113 (45) 1188
104 (40) 1459
95 (35) 1802
86 (30) 2238
77 (25) 2796
68 (20) 3520
59 (15) 4450
50 (10) 5670
41 (5) 7280
32 (0) 9420
23 (- 5) 12,300
14 (- 10) 16,180
5 (- 15) 21,450
- 4 (- 20) 28,680
- 22 (- 30) 52,700
- 40 (- 40) 100,700
(1) Engine Coolant Temperature (ECT) sensor.
(2) Diesel Fuel Temperature (DFT) sensor.
(3) Intake Air Temperature (IAT) sensor.
(4) Measure resistance across sensor terminals.
MAP SENSOR VOLTAGE (1)

Throttle Position Volts
At Idle 1.0-1.5
Wide Open Throttle 4.0-4.9
(1) Measured at sensor, or as seen on scan tool. Ensure sensor output changes instantly when intake manifold vacuum is applied and released.
OXYGEN SENSOR VOLTAGE (1)

Condition Volts
Lean .1
Rich .9
(1) Measure voltage between oxygen sensor ground and signal terminals at PCM.
THROTTLE POSITION (TP) SENSOR VOLTAGE (1)

Throttle Position Volts
At Idle 0.6
Wide Open Throttle Greater Than 4.0
(1) Measured at sensor, or as seen on scan tool.