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HVAC
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c. NOISE WHILE OPERATING A/C SYSTEM
TROUBLESHOOTING HINTS
Magnetic clutch operation noise-Step 4
A/C compressor vane noise -Step 5-13
A/C compressor slippage noise -Step 14-17
Hose or refrigerant line interference noise -Step 18
1
Inspect 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 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 next step.
3
Inspect A/C compressor interference noise
Is there a rattling or vibrating sound
(Inter-
ference noise)?
Yes
Go to Step 18.
No
Go to next step.
4
Inspect magnetic clutch operation noise
Is there 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.
No
Condition is normal. (
Recheck malfunction
symptoms.)
5
Inspect A/C compressor noise time
Is noise heard continuously for more than
3 seconds after A/C compressor comes
on?
Yes
Go to next step,
No
Condition is normal.
(Noise occurs for 2-3
seconds immediately after A/C compressor
turns on.)
6
Inspect idle speed Is it okay?
Yes
Go to next step.
No
Adjust idle speed, then go to Step 19.
7
Inspect refrigerant amount. See refrigerant
system service procedures, refrigerant
charge check
Is it okay?
Yes
Go to Step 10.
No
Go to next step.