Air Conditioning System Check

Air Conditioning System Check

To ensure that system diagnosis is done accurately and smoothly, read Precautions in Diagnosing Trouble Precautions in Diagnosing Trouble
and follow Air Conditioning System Check.
1.
Customer complaint analysis

Perform "Customer Complaint Analysis".

Was customer complaint analysis performed according to instruction?
YES -
Go to Step 2.
NO -
Perform customer complaint analysis.

2.
Visual inspection

Perform "Visual Inspection".

Is there any faulty condition?
YES -
Repair or replace malfunction part.
NO -
Go to Step 3.

3.
DTC check

Perform "DTC Check".

Is it malfunction code?
YES -
Go to Step 4.
NO -
Go to Step 5.

4.
Troubleshooting for DTC

Check and repair according to DTC diag. flow.

Are check and repair completed?
YES -
Go to Step 7.
NO -
Check and repair malfunction part(s).

5.
Check for intermittent problem

Check for intermittent problem.

Is there faulty condition?
YES -
Repair or replace malfunction part(s).
NO -
Go to Step 6.

6.
Air conditioning system symptom diagnosis

Inspect and repair referring to A/C System Symptom Diagnosis A/C System Symptom Diagnosis.

Are inspect and repair complete?
YES -
Go to Step 7.
NO -
Inspect and repair malfunction part(s).

7.
Final confirmation test

Perform DTC check.

Is there any DTC?
YES -
Go to Step 4.
NO -
Air Conditioning system is good condition.

Customer Complaint Analysis

Record details of the problem (failure, complaint) and how it occurred as described by the customer.

For this purpose, use of such a questionnaire form as shown in figure will facilitate collecting information to the point required for proper analysis and diagnosis.

Customer questionnaire (example)





NOTE:

The form is a standard sample. It should be modified according to conditions characteristic of each market.

Visual Inspection

As a preliminary step, be sure to perform visual check of the items that support proper function of the air conditioning system referring to Visual Inspection Visual Inspection.

DTC Check

Refer to DTC Check DTC Check
for checking procedure.

Troubleshooting for DTC

Based on the DTC indicated in Step 4 and referring to applicable DTC flow, locate the cause of the trouble, namely in a sensor, actuator, wire harness, connector, HVAC control module or other part and repair or replace faulty parts.

Check for Intermittent Problem

Check parts where an intermittent trouble is easy to occur (e.g., wire harness, connector, etc.), referring to Intermittent and Poor Connection Inspection Intermittent and Poor Connection Inspection.

Air Conditioning System Symptom Diagnosis

Check the parts or system suspected as a possible cause referring to A/C System Symptom Diagnosis A/C System Symptom Diagnosis.

Final Confirmation Test

Confirm that the problem symptom has gone and the air conditioning system is free from any abnormal conditions. If what has been repaired is related to the malfunction DTC, check DTC once and confirm that no DTC is indicated.