Diagnostic system check-auto A/C controls (Auto A/C)

  • If there are no complaints on drivability, do not perform these diagnostic steps unless otherwise instructed in other sections.
  • Check for related Service Bulletins before starting the diagnosis.
  • Do not clear the DTC unless instructed to do so in a diagnostic step.
  • The battery should be fully charged.
  • The battery cable should be normal and securely connected.
  • The auto A/C control unit harness connector should be clean and correctly connected.
  • The auto A/C control unit terminals should be clean and correctly connected.
  • The ground of the auto A/C control unit should be securely connected to the correct position.

1. Scan tool power-up check

1) Connect the scan tool. Does the scan tool power up?

Yes

=>Go to Scan tool communication verification.

No

Go to Scan tool does not power up.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) Scan tool does not power up".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 without DPD) Scan tool does not power up".

Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) Scan tool does not power up".

2. Scan tool communication verification

1) Connect the scan tool.

2) Turn ON the ignition switch.

3) Verify that communication can be established with the auto A/C control unit using the scan tool. Can communication with the auto A/C control unit be established?

Yes

=>Go to DTC verification.

No

Go to Lost communication with the control panel.

Refer to "57.HVAC Control 7A.Troubleshooting(Auto A/C) lost communication with the control panel (models with radar sensor/ stereo camera)".

Refer to "57.HVAC Control 7A.Troubleshooting(Auto A/C) lost communication with the control panel (models without radar sensor and stereo camera)".

3. DTC verification

1) Observe the DTC information with a scan tool. Is a DTC set?

Yes

Go to the applicable DTC diagnosis.

No

=>Go to Customer's concern check.

4. Customer's concern check

1) Check if the customer's concern is related to the systems other than the auto A/C control. Is the customer's concern related to the systems other than the auto A/C control?

Yes

Go to the applicable control system inspection.

No

=>Go to Symptom check.

5. Symptom check

1) Check if the following symptoms are present. Is there any applicable symptom?

  • Mode door cannot be set to a specified mode.
  • Intake actuator does not work.
  • Magnetic clutch is not functioning.
  • Blower motor does not stop operating.
  • Cooling system is not functioning or is weak.
  • Insufficient air flow from the cooling system
  • Blower motor does not operate regardless of the switch position.
  • Blower motor does not function at the "LOW" position.
  • Blower motor does not function at the "MEDIUM LOW" position.
  • Blower motor does not function at the "MEDIUM HI" position.
  • Blower motor does not function at the "HI" position.

Yes

Repair the applicable symptom.

Refer to "208.HVAC 21D.Symptom mode door cannot be set to a specified mode".

Refer to "208.HVAC 21D.Symptom intake actuator does not work".

Refer to "208.HVAC 21D.Symptom magnetic clutch is not functioning".

Refer to "208.HVAC 21D.Symptom blower motor does not stop operating".

Refer to "208.HVAC 21D.Symptom cooling system is not functioning or is weak".

Refer to "208.HVAC 21D.Symptom insufficient air flow from the cooling system".

Refer to "208.HVAC 21D.Symptom blower motor does not operate regardless of the switch position".

Refer to "208.HVAC 21D.Symptom blower motor does not function at the "LOW" position".

Refer to "208.HVAC 21D.Symptom blower motor does not function at the "MEDIUM LOW" position".

Refer to "208.HVAC 21D.Symptom blower motor does not function at the "MEDIUM HI" position".

Refer to "208.HVAC 21D.Symptom blower motor does not function at the "HI" position ".

No

Go to Intermittent conditions of auto A/C control system.

Refer to "208.HVAC 21D.Symptom intermittent conditions of auto A/C control system".

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