NO.9 NOISE WHILE OPERATING A/C SYSTEM

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NO.9 NOISE WHILE OPERATING A/C SYSTEM

B3E070301038W11

9 | Noise while operating A/C system.
DESCRIPTION | • Noise from magnetic clutch, A/C compressor, hose or refrigerant line.
POSSIBLE CAUSE | • Magnetic clutch operation noise (Step 4) • A/C compressor slippage noise (Steps 14-17) • Hose or refrigerant line interference noise (Step 18)

Diagnostic procedure

STEP | INSPECTION | ACTION
--- | --- | ---
1 | INSPECT A/C COMPRESSOR SLIPPAGE NOISE • Is there a squeaking or whirling sound (A/C compressor slippage noise)? | Yes | Go to Step 12.
No | Go to the next step.
2 | INSPECT A/C COMPRESSOR INTERFERENCE NOISE • Is there a rattling or vibrating sound (interference noise)? | Yes | Go to Step 16.
No | Go to the next step.
3 | INSPECT MAGNETIC CLUTCH OPERATION NOISE • Is there a clicking sound (magnetic clutch operation noise)? | Yes | Adjust the clearance between the pressure plate of magnetic clutch and A/C compressor pulley, then go to Step 17. (See MAGNETIC CLUTCH ADJUSTMENT.)
No | Condition is normal. (Recheck malfunction symptoms.) Go to the next step.
4 | INSPECT IDLE SPEED • Inspect idle speed. (See ENGINE TUNE-UP [ZJ, Z6].) (See ENGINE TUNE-UP [LF].) • Is it normal? | Yes | Go to the next step.
No | Follow the repair instruction described in section 01-40, then go to Step 17.
5 | INSPECT REFRIGERANT AMOUNT • Inspect refrigerant amount. • Is it normal? | Yes | Go to Step 8.
No | Go to the next step.

6

INSPECT REFRIGERANT LINES

• Inspect the refrigerant lines.

  - Is the piping free of damage and cracks?
  - Are the piping connections free of oil grime? (Visual inspection)
  - Are piping connections free of gas leakage?
  - Are the piping installation points on the condenser free of gas leakage?
  - Are the piping installation points on the receiver/drier free of gas leakage?
  - Are the piping installation points on the A/C compressor free of gas leakage?
  - Are the piping installation points on the A/C unit free of gas leakage
  - Perform gas leakage inspection using a gas leak tester.

• Are the above items normal?

Yes

Go to the next step.

No | If the piping or A/C component (s) is damaged or cracked, replace them, then go to Step 17. If there is gas leakage, repair or replace connection and replace the condenser*, then go to Step 17.
7 | INSPECT EVAPORATOR PIPING CONNECTIONS IN A/C UNIT FOR GAS LEAKAGE • Are the piping connections for the evaporator in the A/C unit free of gas leakage? | Yes | Adjust refrigerant amount to the specified level, then go to Step 17.
No | If the piping is damaged or cracked, replace it them, then go to Step 17. If there is gas leakage, repair or replace the connecting parts and replace the condenser*, then go to Step 17.
8 | INSPECT TO SEE WHETHER MALFUNCTION IS IN COMPRESSOR OIL OR ELSEWHERE • Add 20 ml {20 cc, 0.8 fl oz} of compressor oil. • Is noise heard when racing the engine? | Yes | Go to the next step.
No | Troubleshooting completed. Explain repair to customer.
9 | INSPECT 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 the A/C compressor, then go to Step 17.
10 | INSPECT 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 17.
No | Go to the next step.
11 | INSPECT A/C COMPRESSOR OIL • Is compressor oil darker than normal and contaminated with aluminum chips? | Yes | Replace the A/C compressor and condenser, then go to Step 17. (Since the A/C compressor may be worn and receiver/drier may be clogged, replacement of the receiver/drier is necessary.)
No | Condition is normal. Recheck malfunction symptoms.
12 | INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C COMPRESSOR OR ELSEWHERE • Is noise heard immediately after the A/C compressor is stopped? | Yes | Replace the A/C compressor, then go to Step 17. (A/C compressor discharge valve left open)
No | Go to the next step.
13 | INSPECT DRIVE BELT • Inspect drive belt. (See DRIVE BELT INSPECTION [ZJ, Z6]) (See DRIVE BELT INSPECTION [LF]) • Is it normal? | Yes | Go to the next step.
No | Adjust or replace drive belt, then go to Step 17.
14 | INSPECT DRIVE BELT CONDITION • Is the drive belt worn? • Does it have foreign material imbedded in it, or have oil on it? | Yes | Remove obstruction, remove oil, or replace the drive belt, then go to Step 17.
No | Go to the next step.
15 | INSPECT MAGNETIC CLUTCH • Inspect the magnetic clutch. (See MAGNETIC CLUTCH INSPECTION [Z6, ZJ].) (See MAGNETIC CLUTCH INSPECTION [LF].) • Is it normal? | Yes | Replace the A/C compressor (excluding the pressure plate, A/C compressor pulley, and stator), then go to Step 17.
No | Replace the magnetic clutch, then go to Step 17.
16 | INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C COMPRESSOR OR REFRIGERANT LINE • Is noise emitted from the A/C compressor? | Yes | Visually inspect the 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.
17 | 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.

  * :
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.