Troubleshooting Climate Units
Troubleshooting climate units
Warning! Follow the safety instructions for work on the air conditioning system. Safety information air conditioning system Safety Information Air Conditioning System.
Note! First read the instructions covering slow and fast leaks. Refer to: Oil air conditioning (A/C) system, filling Oil Air Conditioning (A/C) System, Filling
See general information about A/C system. Refer to: Air conditioning (AC) system, general instructions Air Conditioning (A/C) System, General Instructions
Note! Always plug the pipes and connections when working on the climate control system.
Overview A/C components
Cabin
1. Relay/fuse box11/B
2. Climate control module/ control panel/ passenger compartment temperature sensor (ECC)
3. Sun sensor (ECC)
4. Relay box 15/14
engine compartment
1. Relay box
2. Pressure sensor
3. Receiver drier
4. Condenser
5. Condenser fan
6. AC compressor
Service valves
1. Upper connection:
High pressure side (HP) service valve - Emptying, vacuum pumping and filling
2. Lower connection:
Low pressure side (LP) service valve - Emptying, vacuum pumping
A/C hoses and pipes
1. Hose, compressor-condenser
2. Pipe, condenser-drier
3. Pipe, drier-intermediate coupling
4. Pipe, intermediate coupling-evaporator
5. Hose/pipe, evaporator-compressor
Climate control unit
1. Damper motor air distribution (ECC)
2. Damper motor temperature (ECC)
3. Damper motor recirculation (ECC, MCC)
4. Power unit blower fan (ECC)
5. Blower fan relay (max relay)
6. Blower fan
Climate unit, intermediate section
1. Temperature sensor evaporator (ECC, MCC)
2. Temperature sensor coolant (ECC)
3. Temperature sensor outdoor temperature (ECC)
Overview A/C system
Refrigerant's path
1. Compressor
2. Condenser
3. Cooling fan
4. Receiver drier
5. Expansion valve
6. Evaporator
7. Blower fan
Explanations:
- A - High pressure, hot liquid
- B - Low pressure, cold liquid
- C- Low pressure, cold gas
- D - High pressure, hot gas
- Dark arrow - Hot air
- Light arrow - Cold air
Troubleshooting consists of three sub procedures in total with a number of steps in each. Not all steps need to be performed if the fault has been rectified before.
Troubleshooting step 1 of 3
General checks
1. Place the car at room temperature (approx. 20 C°).
2. Connect VIDA diagnostic Reading off Volvo Diagnostics Diagnostic Functions and download the AC check software 3132499831324998and check:
• Temperature sensor evaporator
• Temperature sensor passenger compartment
• Temperature sensor outdoor temperature
• sun sensor
3. Manually check:
• the damper motors/dampers: temperature/temperature sides, defroster, ventilation, floor and recirculation
4. Check the blower fan speeds.
5.
7.
9. Check condenser cleanliness.
Troubleshooting step 2 of 3
Carry out performance test on climate units, see: Performance test Performance Test
Troubleshooting step 3 of 3
Measuring the pressure
Use pressure manometer stand: 981 4092 Pressure gauge set 981 4092 Pressure gauge set
- Measure the pressure on the service valves for the high and low pressure sides.
- Before connecting the pressure manometer to the car's service valves, turn both knobs clockwise (-) to their limit positions.
- Connect the pressure manometer to the service valves and hang it up at the bonnet opening. Start and run the engine at idle.
- The inner adjustment of the climate controls are the same as under step 2 performance test.
- Read off the values when the A/C has stabilised after about 8 minutes.
Explanation
- If the pressure values are outside the permitted values in the tables, the cause must be established.
- F = Fixed displacement- respectively V = Variable displacement compressor, ( B4184SM/SJ )
- The following 6 tables represent all fault symptoms on Volvo Cars A/C systems with two service valves, with tips, results and actions in order of priority.
