Pinpoint Tests FB: Ambient Air Temperature (AAT): Introduction
WARNING:
TO PREVENT THE RISK OF HIGH-VOLTAGE SHOCK, ALWAYS FOLLOW PRECISELY ALL WARNINGS AND SERVICE INSTRUCTIONS, INCLUDING INSTRUCTIONS TO DEPOWER THE SYSTEM. THE HIGH-VOLTAGE SYSTEM UTILIZES APPROXIMATELY 300 VOLTS DC, PROVIDED THROUGH HIGH-VOLTAGE CABLES TO ITS COMPONENTS AND MODULES. THE HIGH-VOLTAGE CABLES AND WIRING ARE IDENTIFIED BY ORANGE HARNESS TAPE OR ORANGE WIRE COVERING. ALL HIGH-VOLTAGE COMPONENTS ARE MARKED WITH HIGH-VOLTAGE WARNING LABELS WITH A HIGH-VOLTAGE SYMBOL. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY OR DEATH.
This pinpoint test is intended to diagnose the following:
- ambient air temperature (AAT) sensor
- harness circuits: AAT and SIGRTN
- PCM (12A650)
AMBIENT AIR TEMPERATURE (AAT) SENSOR EXPECTED VALUES SPECIFICATIONS
| Temperature |
AAT Sensor Values |
| °C |
°F |
Resistance (K ohms) |
| -40 |
-40 |
9.72 to 9.95 (C-MAX), 314.21 to 351.34 (All Others) |
| -35 |
-31 |
9.36 to 9.60 (C-MAX), 217.37 to 237.85 (All Others) |
| -30 |
-22 |
9.93 to 9.16 (C-MAX), 169.57 to 184.43 (All Others) |
| -25 |
-13 |
8.41 to 8.64 (C-MAX) |
| -20 |
4 |
7.83 to 8.05 (C-MAX), 93.81 to 100.31 (All Others) |
| -15 |
5 |
7.18 to 7.39 (C-MAX), 83.65 to 89.27 (All Others) |
| -10 |
14 |
6.50 to 6.68 (C-MAX) |
| -05 |
23 |
5.80 to 5.96 (C-MAX) |
| 0 |
32 |
5.10 to 5.25 (C-MAX), 31.84 to 33.47 (All Others) |
| 5 |
41 |
4.44 to 4.56 (C-MAX) |
| 10 |
50 |
3.82 to 3.92 (C-MAX) |
| 15 |
59 |
3.27 to 3.34 (C-MAX) |
| 20 |
68 |
2.77 to 2.83 (C-MAX), 12.28 to 12.71 (All Others) |
| 25 |
77 |
2.34 to 2.39 (C-MAX), 9.85 to 10.15 (All Others) |
| 30 |
86 |
1.97 to 2.01 (C-MAX) |
| 35 |
95 |
1.65 to 1.69 (C-MAX) |
| 40 |
104 |
1.38 to 1.42 (C-MAX), 5.25 to 5.41 (All Others) |
| 50 |
122 |
0.97 to 1.00 (C-MAX), 2.45 to 2.53 (All Others) |
| 60 |
140 |
0.69 to 0.72 (C-MAX) |
Courtesy of FORD MOTOR CO.
| Pin |
Circuit |
| 2 |
SIGRTN (Signal Return) |
| 1 |
AAT (Ambient Air Temperature) |
Courtesy of FORD MOTOR CO.
| Pin |
Circuit |
| 10 |
SIGRTN (Signal Return) |
| 9 |
AAT (Ambient Air Temperature) |
Courtesy of FORD MOTOR CO.
| Pin |
Circuit |
| B45 |
SIGRTN (Signal Return) |
| B33 |
AAT (Ambient Air Temperature) |