NO.8 NOISE WHILE OPERATING A/C SYSTEM [FULL-AUTO AIR CONDITIONER]

id0702c1812700

8
Noise while operating A/C system.
DESCRIPTION
•  Noise from magnetic clutch, A/C compressor, hose or refrigerant line.
POSSIBLE CAUSE
•  Magnetic clutch operation noise
•  A/C compressor vane noise
•  A/C compressor slippage noise
•  Hose or refrigerant line interference noise

*  :If there is gas leakage, air enters into the A/C system. The desiccant within the receiver/drier absorbs the moisture from the air and becomes saturated. If the A/C system is used in this condition, the inside of the A/C compressor will begin to rust due to this moisture, which may cause lock up or noise to occur. Therefore, replacement of the receiver/drier is necessary.

Diagnostic procedure

STEP

INSPECTION

ACTION
1
CHECK A/C COMPRESSOR VANE NOISE
•  Is there a jingling, popping, beeping, or buzzing sound (A/C compressor vane noise)?
Yes
Go to Step 5.
No
Go to the next step.
2
INSPECT A/C COMPRESSOR SLIPPAGE NOISE
•  Is there a squeaking or whirling sound (A/C compressor slippage noise)?
Yes
Go to Step 14.
No
Go to the next step.
3
INSPECT A/C COMPRESSOR INTERFERENCE NOISE
•  Is there a rattling or vibrating sound (interference noise)?
Yes
Go to Step 18.
No
Go to the next step.
4
INSPECT MAGNETIC CLUTCH OPERATION NOISE
•  Is there a clicking sound (magnetic clutch operation noise)?
Yes
Adjust clearance between pressure plate of magnetic clutch and A/C compressor pulley, then go to Step 19.
(See MAGNETIC CLUTCH ADJUSTMENT [FULL-AUTO AIR CONDITIONER].)
No
Condition is normal. (Recheck malfunction symptoms.)
5
INSPECT A/C COMPRESSOR NOISE TIME
•  Is noise heard continuously for more than 3 s after A/C compressor comes on?
Yes
Go to the next step.
No
Condition is normal. (Noise occurs for 2—3 s immediately after A/C compressor turns on.)
6
INSPECT IDLE SPEED
•  Inspect idle speed.
•  Is it okay?
Yes
Go to the next step.
No
Follow the repair instruction described in “ENGINE” section, then go to Step 19.
7
INSPECT REFRIGERANT AMOUNT
•  Inspect refrigerant amount.
•  Is it okay?
Yes
Go to Step 10.
No
Go to the next step.
8
INSPECT REFRIGERANT LINES
•  Inspect refrigerant lines.
―  Is piping free of damage and cracks?
―  Are piping connections free of oil grime? (Visual inspection)
―  Are piping connections free of gas leakage?
―  Are piping installation points on condenser free of gas leakage?
―  Are piping installation points on receiver/drier free of gas leakage?
―  Are piping installation points on A/C compressor free of gas leakage?
―  Are piping installation points on A/C unit free of gas leakage?
―  Perform gas leak inspection using gas leak tester.
•  Are above items okay?
Yes
Go to the next step.
No
If piping or A/C component(s) is damaged or cracked, replace then go to Step 19.
If there is gas leakage, repair or replace connection and replace condenser*, then go to Step 19.
9
INSPECT EVAPORATOR PIPING CONNECTIONS IN A/C UNIT FOR GAS LEAKAGE
•  Are piping connections for evaporator in A/C unit free of gas leakage?
Yes
Adjust refrigerant amount to specified level, then go to Step 19.
No
If piping is damaged or cracked, replace then go to Step 19.
If there is gas leakage, repair or replace connection and replace condenser*, then go to Step 19.
10
CHECK TO SEE WHETHER MALFUNCTION IS IN COMPRESSOR OIL OR ELSEWHERE
•  Add 20 ml {20 cc, 0.68 fl oz} of compressor oil.
•  Is noise heard when racing engine?
Yes
Go to the next step.
No
Troubleshooting completed.
Explain repair to customer.
11
CHECK TO SEE WHETHER MALFUNCTION IS IN A/C COMPRESSOR OR ELSEWHERE
•  Drain compressor oil.
•  Is it contaminated with metal particles?
Yes
Go to the next step.
No
Replace A/C compressor, then go to Step 19.
12
CHECK TO SEE WHETHER MALFUNCTION IS SOMEWHERE IN A/C SYSTEM OR ELSEWHERE
•  Is compressor oil whitish and mixed with water?
Yes
Replace entire A/C system (excluding heater), then go to Step 19.
No
Go to the next step.
13
INSPECT A/C COMPRESSOR OIL
•  Is compressor oil darker than normal and contaminated with aluminum chips?
Yes
Replace A/C compressor and condenser, then go to Step 19. (Since A/C compressor may be worn and receiver/drier may be clogged, replacement of receiver/drier is necessary.)
No
Condition is normal. Recheck malfunction symptoms.
14
CHECK TO SEE WHETHER MALFUNCTION IS IN A/C COMPRESSOR OR ELSEWHERE
•  Is noise heard immediately after A/C compressor is stopped?
Yes
Replace A/C compressor, then go to Step 19. (A/C compressor discharge valve left open)
No
Go to the next step.
15
INSPECT DRIVE BELT
•  Inspect the drive belt.
•  Is it okay?
Yes
Go to the next step.
No
Replace the drive belt, then go to Step 19.
(See DRIVE BELT REMOVAL/INSTALLATION [MZR 1.5, MZR 1.6].)
(See DRIVE BELT REMOVAL/INSTALLATION [MZR 2.0, MZR 2.5].)
(See DRIVE BELT REMOVAL/INSTALLATION [MZR 2.0 DISI i-stop].)
(See DRIVE BELT REMOVAL/INSTALLATION [MZR 2.3 DISI Turbo].)
(See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)
(See DRIVE BELT REMOVAL/INSTALLATION [MZ-CD 1.6].)
(See DRIVE BELT REMOVAL/INSTALLATION [MZR-CD 2.2].)
16
INSPECT DRIVE BELT CONDITION
•  Is drive belt worn?
•  Does it have foreign material imbedded in it, or have oil on it?
Yes
Remove obstruction, remove oil, or replace drive belt, then go to Step 19.
No
Go to the next step.
17
INSPECT MAGNETIC CLUTCH
•  Inspect the magnetic clutch.
•  Is it okay?
Yes
Replace A/C compressor (excluding pressure plate, A/C compressor pulley, and stator), then go to Step 19.
No
Replace magnetic clutch, then go to Step 19.
18
CHECK TO SEE WHETHER MALFUNCTION IS IN A/C COMPRESSOR OR REFRIGERANT LINES
•  Is noise emitted from A/C compressor?
Yes
Visually inspect A/C compressor, replace appropriate parts if necessary, then go to the next step.
No
If noise is due to refrigerant lines, repair detached or missing clips, tighten loose bolts, then go to the next step.
19
VERIFY THAT MALFUNCTION SYMPTOM OCCURS AFTER REPAIR
•  Has A/C compressor noise stopped?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.