HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS) > Diagnostic Procedure for Actuators

AIR MIX DOOR ACTUATOR

TROUBLE SYMPTOM:

Outlet air temperature does not change.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK POWER SUPPLY OF AIR MIX DOOR ACTUATOR.

1) Turn the ignition switch to OFF.

2) Disconnect the air mix door actuator connector.

3) Turn the ignition switch to ON.

4) Measure the voltage between the air mix door actuator connector terminal and chassis ground.

Connector & terminal

(B239) No. 3 (+) — Chassis ground (−):

Is the voltage approx. 10 V or more?

Check the power supply circuit.

2.CHECK AIR MIX DOOR ACTUATOR.

1) Disconnect the air mix door actuator connector.

2) Connect the battery negative terminal to the following terminals. Measure the resistance between air mix actuator terminals using a tester.

Connector & terminal

(B239) No. 3 — No. 1:

(B239) No. 3 — No. 2:

(B239) No. 3 — No. 5:

(B239) No. 3 — No. 6:

Is the resistance between 80 — 100 Ω?

Replace the air mix door actuator.

3.CHECK HARNESS BETWEEN AUTO A/C CONTROL MODULE AND AIR MIX DOOR ACTUATOR.

1) Turn the A/C and ignition switch to OFF.

2) Disconnect the auto A/C control module connector.

3) Measure the resistance between auto A/C control module and air mix door actuator connector.

Connector & terminal

(B239) No. 1 — (i88) No. 28:

(B239) No. 2 — (i88) No. 27:

(B239) No. 5 — (i88) No. 26:

(B239) No. 6 — (i88) No. 25:

Is the resistance less than 1 Ω?

Repair the harness between auto A/C control module and air mix door actuator.

4.CHECK POOR CONTACT.

Check poor contact of auto A/C control module and connector.

Is there poor contact in connector?

Repair the connector.

Replace the auto A/C control module.