Outside Temperature Display: Testing and Inspection
Outside Air Temperature Indicator CalibrationNOTE: The outside air temperature sensor test.
The outside air temperature sensor for the indicator is mounted behind the front bumper. Because of this, the temperature reading can be affected by heat reflection from the road, engine heat, and even exhaust from the surrounding traffic. To prevent bogus readings, the display uses a specific logic as shown.
The outside air is warmer than when the ignition switch was turned OFF (ACC or LOCK position):
- If the ignition switch was turned OFF for less than 2 hours, the displayed temperature when you turn the ignition switch to ON (II) stays at the ignition switch-off temperature until the vehicle has gone faster than 18 mph (11 km/h) for 30 seconds, then the display immediately updates to the measured outside air temperature.
- If the ignition switch was turned OFF for 2 hours or more, the displayed temperature when you turn the ignition switch to ON (II) rises 1 degree every minute until the outside air temperature is reached.
The outside air is cooler than when the ignition switch was turned OFF (ACC or LOCK position):
- If the ignition switch was turned OFF for less than 2 hours, the displayed temperature when you turn the ignition switch to ON (II) is the ignition switch-off temperature. The displayed temperature then drops 1 degree every 2 seconds until the reading matches the outside air temperature.
- If the ignition switch was turned OFF for 2 hours or more, the displayed temperature is the measured outside air temperature.
Forced Display
You can also force the indicator to display the measured temperature.
1. Turn the ignition switch to LOCK (0).
2. Removed the No. 13 (7.5 A) fuse from the driver's under-dash fuse/relay box for 60 seconds, then reinstall it.
3. Turn the ignition switch ON (II).
NOTE: After this procedure, reset the power window control unit.
Troubleshooting
If the indicator displays "---" for more than 2 seconds after selecting the outside air temperature display mode, check for an open in the BRN/WHT wire between the gauge and the outside air temperature sensor or the GRY wire between the gauge assembly and the climate control unit.
Calibration
The outside air temperature indicator's displayed temperature can be recalibrated ±3 °F to meet the customer's expectations.
NOTE: This procedure must be done after the temperature sensor stabilizes.
1. Turn the ignition switch ON (II), and make sure the outside air temperature is displayed.
2. Press the select/reset switch button for 10 seconds. While you continue to hold the button, the display will scroll through temperature settings from +3 ° to -3 °F as shown.
3. When the desired correction value appears on the display, release the button, and the recalibrated outside air temperature will be displayed.
Each time a desired correction value is entered, it replaces the previous value.
Example:
Incorrect value = 68 °F
Desired correction value = +2 °F
Corrected value = 70 °F
Desired correction value = -2 °F
Corrected value = 66 °F
NOTE: To recalibrate the display to the true temperature, remove the outside air temperature sensor (A), but leave it connected. Submerge the sensor and a thermometer (B) in a container of ice water (C). Select the calibration mode as described above, then recalibrate the display to the true temperature.