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. If sensor operating range specifications are not available, see TESTS W/CODES article to verify sensor operation.

ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

Temperature - °F (°C)

⁽¹⁾ Ohms

-4 (-20)

15,000-18,000

68 (20)

1000-4000

176 (80)

200-400

248 (120)

50-150

⁽¹⁾	Measure resistance across sensor terminals.

IGNITION SENSOR RESISTANCE

Application	ECM Terminals	Ohms
CRANK	B8 & B16	500-1000
CYL	B7 & B15	500-1000
TDC	B6 & B14	500-1000

INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE ⁽¹⁾

Temperature - °F (°C)

Ohms

-4 (-20)

15,000-18,000

68 (20)

2000-4000

176 (80)

300-400

⁽¹⁾	Measure resistance between sensor terminals.

OXYGEN SENSOR VOLTAGE ⁽¹⁾

Condition

Volts

Lean

Rich

⁽¹⁾	Measure voltage between ground and O2 sensor terminal using a high-impedance DVOM.

THROTTLE POSITION (TP) SENSOR VOLTAGE ⁽¹⁾

Position

Approximate Volts

Fully Closed

0.1-0.5

Fully Open

4.5-4.8

⁽¹⁾	Measure voltage between terminals D11 (positive) and D12 (negative). Voltage should increase smoothly as throttle is opened.

VEHICLE SPEED SENSOR (VSS) VOLTAGE ⁽¹⁾

Model

Approximate Volts

2.5TL

⁽²⁾

⁽¹⁾	Measure voltage between terminals B13 (positive) and A26 (negative).

⁽²⁾	Rotate left front wheel slowly. Voltage should pulse between zero and 5 volts.