How do you know if the clutch or air conditioning compressors are bad?

 

The system of air conditioning in a vehicle has a number of components that work together with each other to supply fresh air passenger cabin. The clutch drives the compressor, which sends the refrigerant to the evaporator where the refrigerant is condensed. The refrigerant travels through the lines and is cooled by the radiator. Cold air is expelled through the vents of air conditioning in the cabin. If one or some of these system components fails, cold air cannot occur. Check the compressor clutch and air conditioning requires a few steps, gauges and tools manuals.

Instructions

  1. Vehicle passes the change to leave it in neutral or park position. Apply the emergency brake. Pop the hood. Connect the positive voltmeter lead to the positive terminal of the battery. Connect the negative lead of the voltmeter to the negative terminal of the battery. Tour scale voltmeter volt meter and read the number. If the battery voltage is below 12.5 volts, the compressor will not turn on. Charge the battery. If you still get a reading low, then you have a battery cell with cut and must be replaced.
  2. Start the engine and let it warm. Stand in front of the compressor of air conditioning in the front of the engine. Use an assistant to turn the AC controls to maximum. Wait for the clutch against AC compressor engages body and turn. If that does not happen, turn off the engine and disconnect the negative battery cable with a socket wrench.
  3. Locate the main fuse box. AC shows the fuse and examines the filament inside the fuse. Replace the fuse if the filament has melted or molten. Locate the AC relay in the fuse box. Replace it with another relay with the same amperage and pin configuration. Connect the negative battery cable with a socket wrench. Start the engine and let your helper turn the AC controls to maximum. If the clutch is engaged, then the fuse or relay is to blame for the failure.
  4. Determine if your vehicle uses antifreeze R12 or R134a. For R12, connects the hose from the underside of a measuring nozzle of AC to the underside of the compressor. The lower side has a 7/16 inch (1.09 cm) screw union. Hose connecting the upper side of the meter to the upper nozzle side compressor having a threaded union 3/8 inch (0.9 cm). R134a coolant type, gauge hose placed above the nozzle of the quick release of 16 mm in the compressor side. Place the gauge hose from the bottom side in the quick release nipple 13 mm in the compressor.
  5. Start the engine and turn the AC controls to maximum. Open the top and bottom of the meter knobs. Look at the reading. The reading of the lower side must be indicated between 25 and 40 pounds per square inch (PSI). The reading of the upper side must be between 200 and 225 PSI. If read outside these limits or shows no load at all, then the circuit breaker inside the compressor is prevented activation clutch tension. AC fully loaded with the correct antifreeze.
  6. Inspect the belt pulley clutch with the engine off. The belt should not be cracked or oil contamination that could cause it to slide out of place. If the slider, the pulley will not achieve sufficient speed to engage the clutch mechanism. Check the belt for proper tension. Do not allow the belt has more than 1/4 inch (0.6 cm) of free play. Loosen the mounting bolts at the base of the AC compressor and the adjusting bolt at the top with a socket wrench. Pull the compressor against the belt to remove excess tension and then tighten the upper and lower compressor bolts.
  7. Place a mechanic stethoscope to probe the top of the fixed part of the clutch while the engine is idling. Have your assistant turn the AC controls to maximum. Pay attention to any internal buzzing or clicking any clutch. If the clutch fails to engage and tour, but electric hum is heard or click inside, it indicates that there is an internal short in the clutch. Listen for excessive bearing noise coming from the clutch or compressor. Shaft bearings worn accumulated resistance in the wiring and the ignition will fail in the clutch. Wade clutch pulley is also a sign of wear on the shaft bearings.
  8. Turn off the engine. Loosen and remove the three bolts holding the clutch outer circular faceplate. Remove the plate and look at the bottom of the board of the clutch shaft bearing. If you see any oil film or oil leaks evident, that means the compressor shaft seal is failing and that is downloading antifreeze system. You must replace the shaft seal and recharge the system.
  9. Disconnect the cable connector on the clutch with the engine off. Clean the contacts on both sides of the cable connector with electrical contact spray and a cotton swab. Start the engine and turn the AC controls to maximum. Ask your assistant hold a jumper wire to the positive terminal of the battery while you connect the wire to the “hot” wire inside the cable connector (on the clutch side). If the clutch cannot be engaged, then that means the clutch has an internal short.