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 can cause driveability problems.

NOTE: All voltage tests should be performed using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure.

AIRFLOW METER RESISTANCE

Terminals	Ohms	°F (°C)
VS & E2 (ES300)	200-600	N/A
VC & E2 (ES300)	200-400	N/A
THA & E2	10,000-20,000	-4 (-20)
THA & E2	4000-7000	32 (0)
THA & E2	2000-3000	68 (20)
THA & E2	900-1300	104 (40)
THA & E2	400-700	140 (60)
THA & E2	200-400	176 (80)
FC & E1	Infinity	N/A

AIRFLOW METER MEASURING PLATE RESISTANCE

Terminals

Ohms

Measuring Plate Position

FC & E1

Infinity

Fully Closed

FC & E1

Zero

Other Than Closed

VS & E2

200-600

Fully Closed

VS & E2 ⁽¹⁾

20-1000

Fully Open

⁽¹⁾	Resistance will change in a wave pattern as measuring plate is opened.

COLD START INJECTOR TIME SWITCH RESISTANCE

Terminals	Ohms	°F (°C)
STA & STJ	25-45	Less Than 59 (15)
STA & STJ	65-85	More Than 86 (30)
STA & Ground	25-85	N/A

COOLANT TEMPERATURE SENSOR RESISTANCE

Temperature	Ohms
-4°F (-20°C)	10,000-20,000
32°F (0°C)	4000-7000
68°F (20°C)	2000-3000
104°F (40°C)	900-1300
140°F (60°C)	400-700
176°F (80°C)	200-400

COOLANT TEMPERATURE SENSOR RESISTANCE

Temperature	Ohms
176°F (80°C)	1480-1580

EGR GAS TEMPERATURE SENSOR RESISTANCE ⁽¹⁾

Sensor Temperature

Ohms

122°F (50°C)

69,000-89,000

212°F (100°C)

12,000-15,000

302°F (150°C)

2000-4000

⁽¹⁾	Measure between sensor terminals with sensor connector disconnected.

INTAKE AIR TEMPERATURE SENSOR RESISTANCE ⁽¹⁾

Terminals

Ohms

°F (°C)

THA & E2

ES300

2000-3000

68 (20)

LS400

200-300

68 (20)

⁽¹⁾	Measure resistance with ECU connector connected.

ISC VALVE RESISTANCE

Terminals	Ohms
B1 & S1 Or S3	10-30
B2 & S2 Or S4	10-30

KNOCK SENSOR RESISTANCE ⁽¹⁾

Terminals

Ohms

Terminal To Body

Infinity

⁽¹⁾	Terminal disconnected. Replace sensor if continuity exists.

MAIN OXYGEN SENSOR HEATER RESISTANCE ⁽¹⁾

Sensor Temperature

Ohms

68°F (20°C)

ES300

11.7-14.3

SC300, SC400 & LS400

5.1-6.3

⁽¹⁾	Measure resistance between terminals +B and HT of oxygen sensor 4-pin connector.

TPS SPECIFICATIONS RESISTANCE

TPS Terminals

Conditions

Ohms

ES300

VTA & E2

⁽¹⁾ Zero

280-6400

IDL & E2

⁽¹⁾ .014" (.35 mm)

5000 Or Less

IDL & E2

⁽¹⁾ .028" (.71 mm)

Infinity

VTA & E2

Throttle Valve Fully Open

200-11,600

VC & E2

N/A

2700-7700

LS400 & SC300

VTA & E2

⁽¹⁾ Zero

200-1200

IDL & E2

⁽¹⁾ .0157" (.40 mm)

2300 Or Less

IDL & E2

⁽¹⁾ .026" (.65 mm)

Infinity

VTA & E2

Throttle Valve Fully Open

3300-10,000

VC & E2

N/A

4000-9000

SC400 (Main)

VTA1 & E2

⁽¹⁾ Zero

200-800

IDL1 & E2

⁽¹⁾ .0157" (.40 mm)

2300 Or Less

IDL1 & E2

⁽¹⁾ .026" (.65 mm)

Infinity

VTA1 & E2

Throttle Valve Fully Open

3300-10,000

VC & E2

N/A

4000-9000

SC400 (Sub)

VTA2 & E2

⁽¹⁾ Zero

200-800

IDL2 & E2

⁽¹⁾ .014" (.35 mm)

2300 Or Less

IDL2 & E2

⁽¹⁾ .022" (.55 mm)

Infinity

VTA2 & E2

Throttle Valve Fully Open

3300-10,000

VC & E2

N/A

4000-9000

⁽¹⁾	Clearance between throttle lever and stop screw.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Engine Controls - Sensor Operating Range Charts: Introduction

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?