Pinpoint Test DY: Engine Oil Temperature (EOT) Sensor: Introduction

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This pinpoint test is intended to diagnose the following:

engine oil temperature (EOT) sensor (12A648)
harness circuits: EOT and SIGRTN
powertrain control module (PCM) (12A650)

Engine oil temperature must be greater than 10°C (50°F) to pass the KOEO self-test and greater than 66°C (150°F) to pass the KOER self-test.

Voltage values calculated for VREF = 5 volts. These values can vary by 15% due to sensor and VREF variations.

Fig 1: Temperature Sensor Voltage And Resistance Characteristic Graph

Courtesy of FORD MOTOR CO.

TEMPERATURE SENSOR VOLTAGE AND RESISTANCE SPECIFICATIONS

Temperature		Temperature Sensor Values
°C	°F	Voltage	Resistance (K ohms)
120	248	0.28	1.18
110	230	0.36	1.55
100	212	0.47	2.07
90	194	0.61	2.80
80	176	0.80	3.84
70	158	1.05	5.37
60	140	1.37	7.70
50	122	1.77	10.97
40	104	2.23	16.15
30	86	2.74	24.27
20	68	3.26	37.30
10	50	3.73	58.75
0	32	4.14	95.85
-10	14	4.45	160.31

Fig 2: Engine Oil Temperature (EOT) Sensor Connector

Courtesy of FORD MOTOR CO.

For PCM connector views or reference values, refer to REFERENCE VALUES .

POWERTRAIN CONTROL MODULE (PCM) CONNECTOR

Connector	Pin	Circuit
170 Pin	E58 B35 E57 E27	SIGRTN VPWR VREF EOT