PINPOINT TEST DJ: Air Conditioning Evaporator Temperature (ACET) Sensor: Introduction

WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

This pinpoint test is intended to diagnose the following:

ACET sensor (19C734)
harness circuits: ACET and SIGRTN
powertrain control module (PCM) (12A650)

AIR CONDITIONING EVAPORATOR TEMPERATURE (ACET) SENSOR

°C	°F	Voltage	Resistance (K ohms)
100	212	0.47	2.08
90	194	0.61	2.8
80	176	0.80	3.84
70	158	1.05	5.34
60	140	1.37	7.55
50	122	1.77	10.93
40	104	2.23	16.11
30	86	2.74	24.25
20	68	3.26	37.34
10	50	3.73	58.99
0	32	4.14	95.85
-10	14	4.45	160.31
-20	-4	4.66	276.96

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

Fig 1: Powertrain Control Module (PCM) (12A650)

Courtesy of FORD MOTOR CO.

Pin	Circuit
1	SIGRTN (Signal Return)
2	ACET (Air Conditioning Evaporator Temperature)

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

Connector	Pin	Circuit
140 Pin	B33, E57 B58, E58 B53	VREF SIGRTN ACET