55A-BLOWER AIR AMOUNT CANNOT BE CHANGED.

Inspection Procedure 3: The blower air volume cannot be changed

COMMENTS ON TROUBLE SYMPTOM

If the blower air volume is not changed by operating the blower switch, the blower switch may be defective.

PROBABLE CAUSES

DIAGNOSIS

STEP 1. Check the heater resistor.

Refer to

Is the heater resistor in good condition?

Go to Step 2

Replace the heater resistor.

STEP 2. Check open circuit in heater resistor line between blower motor connector and heater resistor connector.

Is the check result normal?

Go to Step 3

Repair the connector(s) or wiring harness.

STEP 3. Resistance measurement at the blower switch connector.

(1) Disconnect the connector, and measure at the wiring harness side.

(2) Continuity between terminal 4 and body ground.

OK: Continuity exists (2 Ω or less)

Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Go to Step 4

STEP 4. Check the blower switch.

Refer to

Is the blower switch in good condition?

Go to Step 5

Replace the heater control panel.

STEP 5. Check open circuit in blower switch line between blower motor connector, heater resistor connector blower switch connector, and body ground.

note	Before the wiring harness check, check the junction block connector and joint connector.

Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the connector(s) or wiring harness.