PT Cruiser L4-2.4L Turbo VIN G (2004)
On power up, when the outside temperature sensed by the ATS is warmer than the temperature stored in the module memory, the
Compass/Temperature Module will update the displayed temperature to the outside air temperature within 30 seconds after it has detected that the
vehicle has been moving for 2 minutes.
TEMPERATURE UPDATE - COLD
On power up, when the outside air temperature sensed by the ATS is colder than the stored memory temperature, the Compass/Temperature Module
will update the displayed temperature to the outside temperature at a rate of -1° F every 2 seconds, regardless if the vehicle is moving or not.
EXTREME TEMPERATURE / OPEN OR SHORT CIRCUIT CONDITION
If the measured outside temperature is more than 60° C (140° F) or the ATS sense circuit is shorted to ground, the temp display will be 60° C (140°
F) to indicate a short circuit condition.
If the measured outside temperature is less than -45° C (-49° F) or the ATS sense circuit is open, the temp display will be -45° C (-49° F) to indicate
an open circuit condition.
AMBIENT TEMPERATURE SENSOR
The ambient air temperature is monitored and displayed by the Compass/Temp Module. The Compass/Temperature Module receives a hardwire input
from the ambient temperature sensor (ATS). The ATS is mounted on the center support brace in front of the A/C condenser, behind the front grille.
The ATS cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
The ATS is a variable resistor that operates on a 5-volt reference signal circuit hardwired from the Compass/Temperature Module. The resistance in
the ATS changes as the outside temperature rises or falls. The Compass/Temperature Module senses the change in reference voltage through the ATS
resistor. Based on the resistance of the ATS, the Compass/Temperature Module is programmed to correspond to a specific temperature. The
Compass/Temperature Module then displays the proper ambient temperature.
DIAGNOSIS AND TESTING
SELF-CHECK DIAGNOSTICS
1. With the ignition switch in the OFF position, depress and hold the STEP button.
2. Turn the ignition switch to the ON position and release the STEP button.
3. All of the VFD segments will illuminate for 2-4 seconds. Check for segments that do not illuminate or illuminate all the time.
4. The self-check is complete when an F (FAIL), or a P (PASS) is displayed. If an F is displayed, the overhead console must be replaced. The
Compass/Temperature Module will not display an F for a VF segment that does not illuminate.
5. To exit the self-check mode, depress the STEP button or cycle the ignition switch and the Compass/Temperature Module will return to normal
operation.
AMBIENT TEMPERATURE SENSOR
The outside temperature function is supported by the ambient temperature sensor (ATS), a signal and ground circuit hardwired to the compass/temp
module, and the display.
If the display indicates 60° C (140° F) or the ATS sense circuit is shorted to ground, the temp display will be 60° C (140° F) to indicate a SHORT
circuit condition.
If the display indicates -45° C (-49° F) or the ATS sense circuit is open, the temp display will be -45° C (-49° F) to indicate an OPEN circuit
condition.
If there is an OPEN or SHORT circuit condition, it must be repaired before the VF display can be tested.
The ATS can be diagnosed using the following Sensor Test. Test the ATS circuits using the diagnostics in Testing and Inspection. If the ATS and the
circuits are confirmed to be OK, but the temperature display is inoperative or incorrect, replace the Compass/Temperature Module.
AMBIENT TEMPERATURE SENSOR TEST
1. Turn the ignition OFF.
2. Disconnect and isolate the battery negative cable.
3. Disconnect the ATS harness connector.
4. Measure the resistance of the ATS using the following min/max values:
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0° C (32° F) Sensor Resistance = 29.33 - 35.99 Kilohms
-
10° C (50° F) Sensor Resistance = 17.99 - 21.81 Kilohms
-
20° C (68° F) Sensor Resistance = 11.37 - 13.61 Kilohms
-
25° C (77° F) Sensor Resistance = 9.12 - 10.86 Kilohms
-
30° C (86° F) Sensor Resistance = 7.37 - 8.75 Kilohms
-
40° C (104° F) Sensor Resistance = 4.90 - 5.75 Kilohms
