The AAT Sensor is a thermistor type sensor with a variable resistance that produces an analog signal between 0 and 5 V, representing the temperature of the ambient air. The AAT Sensor (see Figure “Ambient Air Temperatures Sensor Dimensions” ) is used with the Idle Shutdown Timer, specifically for the Ambient Air Temperature Override Disable feature or for Optimized Idle.
Ambient Air Temperature Sensor Installation
Install the AAT Senaor where ambient air temperature can be read. A protected location on the frame rails where it will not be splattered with dirt and grime and is removed from any heat source such as exhaust is preferred. See Figure “Ambient Air Temperature Sensor Installation” for AAT Sensor installation.
| Label | CPC Connector #3, 21–pin (1) | Wire Color | Ambient Air Temperature Connector (2) Cavity |
| Sensor Return #1. | 3/2 | YEL/BLK | A |
| Ambient Air Temp | 3/15 | TAN/YEL | B |
Figure 3. Ambient Air Temperature Sensor Installation
The parameter for the AAT Sensor are listed in Table “Ambient Air Temperature Sensor Parameters” .
| Parameter Group | Parameter | Options | Default | Access |
| 31 | Ambient Air Temp Sensor Enable | 0 – Not Available
1 – Hardwired 2 – Reserved for J1939 3 – J1587 4 – ECAN |
0 – Not Available | VEPS, DRS 7.0 |
| 31 | MID for Ambient Air Temp | 0 — 255 | 0 | VEPS, DRS 7.0 |
