NO.9 NOISE WHILE OPERATING A/C SYSTEM


BHE070301038W11

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 3)
• A/C compressor slippage noise (Steps 4-6)
• Hose or refrigerant line interference noise (Step 7)

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 4.
No
Go to next step.
2

INSPECT A/C COMPRESSOR INTERFERENCE NOISE

• Is there a rattling or vibrating sound (interference noise)?
Yes
Go to Step 7.
No
Go to next step.
3

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 8.
No
Condition is normal. (Recheck malfunction symptoms.)
4

INSPECT DRIVE BELT

• Inspect drive belt.
• Is it normal?
Yes
Go to next step.
No
Adjust or replace drive belt, then go to Step 8.
5

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 8.
No
Go to next step.
6

INSPECT MAGNETIC CLUTCH

• Inspect magnetic clutch.
• Is it normal?
Yes
Replace A/C compressor (excluding pressure plate, A/C compressor pulley, and stator), then go to Step 8. (See A/C COMPRESSOR REMOVAL/INSTALLATION.)
No
Replace magnetic clutch, then go to Step 8.
7

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 next step.
No
If noise is due to refrigerant lines, repair detached or missing clips, tighten loose bolts, then go to next step.
8

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.