Air Conditioning System Check

Air Conditioning System Check

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

Step 1-7:

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)

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 for checking procedure. DTC Check

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

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.