HVAC - Lack of Temperature Control

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NUMBER: 91-T-202

CORP.REF.NO: 101105

DATE: October 1991

SECTION: 1C, 8A


SUBJECT:
LACK OF HVAC TEMPERATURE CONTROL
- CORRECTIONS

MODELS/YEARS:
1991 NINETY-EIGHT TOURING SEDAN


CONDITION: Some 1991 Ninety-Eight/Touring Sedans may experience HVAC air temperature being too warm during cold weather and/or too cold during warm weather, which may be caused by a pinched incar sensor hose, in-car sensor seal not sealing to instrument panel, or a defective outside temperature sensor.

CORRECTIONS:

Pinched in-Car Sensor Hose

1. Remove glove box tray to gain access to sensor hose.
2. Disconnect sensor hose at the plastic connector located near the instrument panel support bracket.
3. Pull the aspirator hose from the pinch point at the A/C duct to defrost duct interface.
4. Cut and remove the damaged portion of the hose and reconnect the remaining length.

In-Car Sensor Seal Not Sealing to Instrument Panel

1. Remove cluster trim plate.
2. Remove HVAC control head and radio.
3. Loosen both in-car sensor attaching screws and push down on the sensor while re-tightening the screws to seal the sensor to the instrument panel.

Defective Outside Temperature Sensor

1. Check resistance of outside temperature sensor. Resistance should be within 25 ohms of the values shown below for the temperature at which you are checking the sensor:

18 degrees C (65 degrees F) 1380 ohms
24 degrees C (75 degrees F) 1050 ohms
29 degrees C (85 degrees F) 840 ohms

2. If not within the above specifications, replace defective sensor.