Overview

IMI Air Conditioning System Fault Diagnosis

Who is it for?
This course is designed to develop technicians’ diagnostic capabilities in automotive heating, ventilation, and air conditioning (HVAC) systems. With increasing complexity in climate control systems and rising environmental obligations, accurate and efficient fault diagnosis is critical. Technicians must understand both mechanical and electronic systems to service and repair AC faults safely and effectively.

The course builds on existing F-Gas qualifications and focuses on expanding diagnostic competence in line with current technologies, refrigerants (R134a and R1234yf), and environmental regulations.

Entry Requirements/Prerequisites
Candidates must hold one of the following:

• IMI Level 3 Award in Automotive Refrigerant Handling (EC842-2006) (VRQ) (500/6771/0)
• Equivalent F-Gas qualification meeting regulatory requirements

To ensure a common baseline, learners will undertake a recap and initial assessment of the core learning outcomes from the Refrigerant Handling qualification, including:

• A/C system operation and components
• Environmental impact and properties of fluorinated gases
• Relevant EC regulations (842/2006 and 2006/40/EC)
• Recovery and handling procedures for refrigerants
• Safe operation of service equipment and cylinders

Learning Outcomes
By the end of the course, learners will be able to:

1. Identify common HVAC faults, symptoms, and causes
2. Use A/C manifold gauge sets for pressure diagnosis
3. Determine if system is operational by measuring temperature differences
4. Perform leak detection checks using:
• Oxygen-free nitrogen (OFN) charging and leak detection spray
• Listening devices/diagnostic stethoscopes
• Electronic and UV leak detector kits
5. Test and interpret readings from key electrical and electronic components:
• A/C compressor electromagnetic clutch or variable displacement solenoids
• Engine cooling fan circuits
• Refrigerant pressure sensors
• HVAC blower motors and control circuits
• HVAC flap actuators and position sensors
• Ambient air and vent temperature sensors
6. Understand integration of A/C with engine management systems and identify interactions that may disable operation
7. Interpret fault codes and scan tool live data
8. Use OEM technical data and wiring diagrams for diagnosis
9. Evaluate system performance and verify correct operation post-repair