SELF-DIAGNOSTICS
A/C control assembly monitors system circuits and stores codes in memory if problems are detected. All codes are stored in memory except Codes 22 and 23. Malfunction is current if Code 22 or 23 is displayed. To retrieve stored codes, see RETRIEVING CODES . Codes are displayed at A/C control assembly driver's side temperature display.
TESTING
| WARNING | To avoid injury from accidental air bag deployment, read and carefully follow all SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM procedures in AIR BAG RESTRAINT SYSTEM article. |
EVAPORATOR TEMPERATURE SENSOR TESTING
Remove evaporator temperature sensor. Measure sensor resistance at temperatures specified. See EVAPORATOR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS table. If resistance is not as specified, replace sensor.
| Sensor Temperature °F (°C) | (1) Ohms |
|---|---|
| 32 (0) | 4600-5200 |
| 59 (15) | 2000-2700 |
| (1) As temperature increases, resistance should gradually decrease. | |
| (1) | As temperature increases, resistance should gradually decrease. |
EVAPORATOR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS
PRESSURE SWITCH TESTING
- Locate pressure switch near receiver-drier. (Scheme 1) Connect A/C manifold gauge set. Start engine. Turn blower and A/C on. Observe system pressure. With pressure switch connector disconnected, test for continuity between pressure switch terminals No. 1 and 4.
- Continuity should not exist if high side pressure is less than 326 psi (23 kg/cm 2 ) or higher than 455 psi (32 kg/cm 2 ). Continuity should exist if high side pressure is greater than 326 psi (23 kg/cm 2 ) or lower than 455 psi (32 kg/cm 2 ). If continuity is not as specified, replace pressure switch.
