Factors Affecting Accuracy

Various internal and external conditions can affect compass accuracy.

• Magnetic mount devices (antennas, racks, etc.) should not be located near the magnetic sensor. Use of these devices near the sensor will cause the compass to be inaccurate. If these devices must be used, the compass should be recalibrated using the zone and calibration adjustments.
• Driving near power lines or objects with high iron or steel content (bridges, underground pipes and tunnels, etc.) may temporarily change the compass heading. The display will return to the true vehicle heading after the vehicle leaves the area.
• In most locations, magnetic north differs from the "true north" direction shown on maps (geographic north). This difference changes considerably across the country anywhere from 25 degrees to the east to 30 degrees to the west. This misalignment can be corrected on the compass by performing the Zone Adjustment procedure described in the Adjustments portion of this section.

The temperature display operates through the use of a thermometer sensor (15A022) mounted behind the front bumper/grille. The display can be changed from English to metric units.

To update the temperature, the module processes data from the sensor to make sure engine heat does not affect the displayed temperature. Upon starting the vehicle, the module checks the temperature and how long the ignition switch has been off. These parameters are described by one of three groups below.

Engine Cold

If ignition has been on for less than five minutes, and was previously off for longer than two hours, the engine is cold and does not affect the temperature sensor. Current sensor data is used.

Engine Warm, Updated Temperature Cooler

If ignition has been on for longer than five minutes or if the ignition was off for less than two hours, the engine compartment may be warm from the heat of the engine. The current temperature is displayed only if it is less than the stored temperature reading.

Engine Warm, Updated Temperature Warmer

If the sensor data indicates a higher temperature, the module uses a high-speed counter to monitor vehicle speed to determine whether engine heat is causing erroneous readings. The counter is incremented when the speed is greater than 53 km/h (33 mph) and decremented when the speed is between 16 and 53 km/h (10-33 mph). If the speed is less than 16 km/h (10 mph), the counter is reset, and the displayed temperature is not updated from its last reading. If the counter is greater than two minutes, the currently sensed temperature is displayed. If the high-speed counter has counted less than two minutes, the temperature can increase only one degree per minute.

If the temperature sensor is short- or open-circuited, the display will read SC or OC, respectively. If the temperature drops below 3°C (38°F), or is below 3°C (38°F) upon power-up, the display will alternate between displaying ICE and the temperature. The display will alternate every two seconds for a time of one minute.