SAAB WIS ONLINE

EVAPORATOR SENSOR

EVAPORATOR SENSOR

WIRING DIAGRAM:


CHECK EVAPORATOR SENSOR.

Turn the ignition switch to OFF.

Remove the glove box.

Disconnect the connector from evaporator sensor.

Measure the resistance between connector terminals of evaporator sensor.

Terminals

No. 1 — No. 2:

Is the resistance approx. 3.3 kΩ at 20°C (68°F)?

Yes


No

Replace the evaporator sensor.


CHECK INPUT SIGNALS FOR EVAPORATOR SENSOR.

Turn the ignition switch to ON.

Measure the voltage between (B256) connector terminal and chassis ground.

Connector & terminal

(B256) No. 2 (+) — Chassis ground (−):

Is the voltage approx. 5 V?

Yes


No


CHECK OUTPUT SIGNALS FROM AUTO A/C CONTROL MODULE.

Turn the ignition switch to OFF.

Pull out the auto A/C control module.

Turn the ignition switch to ON.

Measure the voltage between auto A/C control module connector terminals.

Connector & terminal

(B283) No. 7 (+) — No. 17 (−):

Is the voltage approx. 5 V?

Yes


No


CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND EVAPORATOR SENSOR.

Turn the ignition switch to OFF.

Disconnect the connectors from auto A/C control module.

Measure the resistance of harness between auto A/C control module and evaporator sensor.

Connector & terminal

(B256) No. 2 — (B283) No. 7:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between auto A/C control module and evaporator sensor.


CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND EVAPORATOR SENSOR.

Measure the resistance of harness between auto A/C control module and evaporator sensor.

Connector & terminal

(B256) No. 1 — (B283) No. 17:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between auto A/C control module and evaporator sensor.


CHECK POOR CONTACT IN AUTO A/C CONTROL MODULE CONNECTOR.

Check poor contact in auto A/C control module connector.

Is there poor contact in connector?

Yes

Repair the connector.


No

Replace the auto A/C control module.