A/C - Produces Only Warm Air From Vents
NUMBER: 24-003-07GROUP: Heating & Air Conditioning
DATE: May 01, 2007
SUBJECT:
Only Warm Cabin Air Output From HVAC System
OVERVIEW:
This bulletin involves the infrared (IR) temperature sensor used on automatic temperature control (A/C).
MODELS:
2007 (HB/HG) Durango/Aspen
2008 (JS27) Sebring Convertible
2007 (JS41) Sebring
2008 (JS41) Avenger
NOTE:
This bulletin applies to vehicles equipped with an Automatic Temperature Control system (sales code HAB for JS or HAF for HB/HG) and built on or before March 27, 2007 (MDH 0327XX).
SYMPTOM/CONDITION:
The customer may notice, while in automatic temperature control mode, that the driver and front passenger cabin air output from the HVAC system remains warm. Adjusting the HVAC temperature settings, while in the automatic temperature control mode, to a cooler temperature will not change the warm cabin air output. The warm cabin air output can also occur when operating in manual temperature control mode, with the exception of the full cold (LO) temperature selection.
When in automatic or manual temperature control, all HVAC modes (defrost, floor, bi-level, etc.) operate as designed. This condition may be due to the HVAC system infrared (IR) temperature sensor that "locks" at one temperature and fails to change.
DIAGNOSIS:
1. Connect the StarSCAN(R) to the vehicle Diagnostic Link Connector (DLC).
2. Turn the ignition switch to the "ON" position. Power up the StarSCAN(R).
3. If the vehicle is a HB/HG:
a. From the StarSCAN(R) Main Menu select "ECU View".
b. Select "HVAC Heat, Ventilation, and Air Conditioning".
c. Select "Data Display".
d. Scroll down to "Bussed Inputs".
e. Scroll down to "I/R Sensor On Time".
f. Monitor the current reading for the "I/R Sensor On Time" (displayed in milliseconds).
4. If the vehicle is a JS:
a. From the StarSCAN(R) Main Menu select "ECU View".
b. Select "HVAC Heat, Ventilation, and Air Conditioning".
c. Select "Data Display".
d. Scroll down to "I/R Temp".
e. Monitor the current temperature reading for the "I/R Temp".
5. While monitoring "I/R Sensor On Time" or "I/R Temp" reading, place a finger over the face of the infrared sensor (located in the overhead console or windshield header). The "I/R Sensor On Time" or "I/R Temp" reading should change rapidly as a finger is placed on and off of the infrared sensor. A suspect I/R sensor will not change reading.
6. Did the "I/R Sensor On Time" or "I/R Temp reading change?
a. If YES >>>> then STOP. This bulletin does not apply. Further diagnosis is required.
b. If NO >>>> then perform the Repair Procedure.
7. Turn the ignition switch to the "OFF" position.
PARTS REQUIRED:
SPECIAL TOOLS/EQUIPMENT REQUIRED:
REPAIR PROCEDURE:
1. Replace the infrared sensor. For detailed repair procedures refer to TechCONNECT. Select the SERVICE INFO tab, then: 24 - Heating and Air Conditioning / 24 - HVAC - Service Information / Controls - Front / Sensor - Infrared / Removal and Installation.
2. Verify that the infrared sensor face is centered to the hole in the overhead console.
3. Verify that the "I/R Sensor On Time" reading changes when a finger is placed over the face of the sensor.
POLICY:
Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
FAILURE CODE:
Disclaimer:
This bulletin is supplied as technical information only and is not an authorization for repair.