Engine Coolant Temperature (ECT) Sensor

ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE (EXCEPT B2300,B2500, B3000, B4000 & TRIBUTE)

Temperature °F (°C)

Ohms

Miata ⁽¹⁾

68 (20)

2270-2740

176 (80)

290-340

Millenia & Protege ⁽²⁾

68 (20)

2200-2600

176 (80)

290-340

MPV ⁽²⁾

68 (20)

2200-2800

176 (80)

290-400

626 ⁽²⁾

68 (20)

35,500-39,200

140 (60)

7180-7920

⁽¹⁾	Measure resistance between ECT sensor terminals "A" and "C". See Fig 1.

⁽²⁾	Measure resistance between ECT sensor terminals.

ENGINE COOLANT TEMPERATURE (ECT) SENSOR SPECIFICATIONS (B2500, B3000, B4000 & TRIBUTE 3.0L)

Temperature °F (°C)

⁽¹⁾ PID Voltage

Ohms

50 (10)

3.51

58,750

68 (20)

3.07

37,300

86 (30)

2.60

24,270

104 (40)

2.13

16,150

122 (50)

1.70

10,970

140 (60)

1.33

7700

158 (70)

1.02

5370

176 (80)

0.78

3840

194 (90)

0.60

2800

212 (100)

0.46

2070

230 (110)

0.35

1550

248 (120)

0.27

1180

⁽¹⁾	Check sensor voltage using New Generation Star (49 T088 0A0) scan tool connected to Data Link Connector (DLC) 2. DLC is located under left side of instrument panel, right of steering column.

Fig 1: Identifying ECT Sensor Terminals (Miata)

Courtesy of MAZDA MOTORS CORP.