THIS IS THE TEST PROCEDURE FOR A 2000 OUT OF THE SERVICE MANAUAL:
Compass Accuracy
Magnetic mounted devices like antennas and luggage racks should not be located on the front third of the vehicle roof. Placing these devices near the compass will cause inaccurate directional readings. If these devices must be used, accuracy may be improved by recalibrating the compass while the devices are installed on the vehicle.
Driving near power lines, or driving in the area of large iron or steel structures can temporarily change the compass' heading. If the compass remains inaccurate after driving near such objects, demagnetize the vehicle and recalibrate the compass.
Most geographic areas (zones) have a magnetic north compass point that varies slightly from the northerly direction on maps. This variation is four degrees between the adjacent zones and will become noticeable as the vehicle crosses multiple zones. A correct zone setting eliminates the error. Refer to «Compass Zone Adjustment».
Temperature, Outside Air
The thermometer sensor (15A022) is attached to the radiator frame behind the grille. The temperature can be displayed in centigrade or Fahrenheit by pressing the MODE switch.
If the outside temperature falls below 3.3ºC (38ºF), the display will alternate from "ICE" to the outside temperature at a two second rate for one minute.
The outside air temperature reading can be affected by engine heat when the vehicle is idling or has been off for less than two hours. The compass and thermometer (19A548) will limit the increase of the displayed temperature to one degree per minute at very low speeds or immediately after the ignition is turned on. After two minutes at a sustained speed of at least 53 km/h (33 mph), effects of engine heat are minimal and the compass will display the current outside temperature reading. Temperature decreases are always updated immediately.
If the outside air temperature sensor is short or open circuited, then the display will show 60ºC (140ºF) or -40ºC (-40ºF) respectively in place of temperature.
B2 CHECK THERMOMETER SENSOR FUNCTION
1 Remove the thermometer sensor.
Measure the resistance between thermometer sensor terminal 1 and terminal 2 at an ambient temperature of 18º-29.5ºC (65º-85ºF). Check for intermittent readings.
l Is the resistance between 8,000 ohms and 14,000 ohms?
è Yes
Go to «B3».
è No
REPLACE the thermometer sensor. TEST the system for normal operation.
B3 CHECK SENSOR CIRCUIT FEED FOR OPEN
Measure the resistance between compass and thermometer C342-9, circuit 233 (DB/Y), and thermometer sensor C194-1, circuit 233 (DB/Y).
l Is the resistance less than 5 ohms?
è Yes
Go to «B4».
è No
REPAIR circuit 233 (DB/Y) and/or BK wire to compass and thermometer C902-5. TEST the system for normal operation.