AC Chapter 10

Low voltage at the compressor clutch coil could cause

A and B

If the compressor oil has been drained and it shows signs of metallic particles, all of the following should be done, EXCEPT:

A full charge of heavier refrigeration oil should be added after flushing

Compressor clutch controls are being discussed. Technician A says a clutch may be cycled on and off based on system pressure. Technician B says some clutches will not be cycled on-off unless the driver operates the manual air conditioning control device. Who is correct?

Both Tech

Technician A says a replacement compressor should have the same type of clutch and pulley as the old compressor. Technician B says the mounting brackets and other fasteners on a replacement compressor should be identical to those on the old compressor. Who is correct?

Both tech

A technician finds an air conditioning clutch will not engage. Upon initial testing the compressor is receiving both proper power and ground at the compressor clutch electrical connector, in addition the compressor input shaft turns freely by hand. Which of the following is the most likely cause?

Compressor clutch air gap too large.

The compressor clutch circuit is being tested. Technician A says if the test lamp does not light when connected across the clutch's harness terminals, then the problem is probably a shorted clutch coil. Technician B says a test lamp that flickers or goes out may indicate the PCM or other control device is defective. Who is correct?

Tech B

Technician A says low pressure exists in an operating air conditioning system from the metering device outlet to the compressor inlet. Technician B says that high pressure exists in an operating air conditioning system from the compressor outlet to the metering device inlet. Who is correct?

Tech B (wrong)

When the A/C switch is in the off position on a vehicle with a cycling clutch type system the compressor clutch stays engaged. Which of the following is the most likely cause?

The compressor clutch relay is stuck closed.

The A/C compressor clutch will not engage but the technician finds normal battery voltage at the compressor clutch connector. Which of the following is the most likely cause?

Too great a compressor clutch air gap.

All of the following statements about variable displacement compressors are true, EXCEPT:

Variable displacement compressors do not have a cycling clutch. (wrong)

Technician A says most compressor clutches are driven from the engine crankshaft by a belt. Technician B says late model hybrid electric vehicles use an integrated electric motor to drive the compressor. Who is correct?

both tech

Compressor clutch controls are being discussed. Technician A says a clutch may be cycled on and off based on system pressure. Technician B says some clutches will not be cycled on-off unless the driver operates the manual air conditioning control device. Who is correct?

both techs

Technician A says when the compressor oil is drained, the oil can be reused if it looks good. Technician B says the type of new oil installed or added is not important as long as the compressor has enough oil. Who is correct?

neither

Replacement compressors are being discussed. Technician A says after installing a replacement compressor the receiver drier/accumulator should also be replced. Technician B says the replacement compressor is supplied with oil, and checking the level is not necessary. Who is correct?

tech a

The compressor pumps refrigerant as a

vapor