Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
DEFINITION: Noise originating from the A/C compressor, drive belt or the A/C lines. | |||||||||
1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Automatic or Symptoms - HVAC Systems - Manual | ||||||
2 |
Is a screeching, squealing noise heard when the A/C is engaged? | Go to Step 3 | Go to Step 9 | ||||||
3 | With the engine OFF, inspect the drive belt for excessive wear. Refer to Drive Belt Falls Off and Excessive Wear Diagnosis for the 4.6L engine or Drive Belt Falls Off and Excessive Wear Diagnosis for the 3.9L engine. Is the drive belt excessively worn? | Go to Step 18 | Go to Step 4 | ||||||
4 | Inspect the drive belt tension. Refer to Drive Belt Tensioner Diagnosis for the 4.6L engine or Drive Belt Tensioner Diagnosis for the 3.9L engine. Is the drive belt tension correct? | Go to Step 5 | Go to Step 19 | ||||||
5 | Inspect the drive belt for excessive oil coverage. Is the drive belt covered with oil? | Go to Step 17 | Go to Step 6 | ||||||
6 |
Is the A/C compressor locked up? | Go to Step 23 | Go to Step 7 | ||||||
7 | Is the A/C compressor clutch slipping? | Go to Step 23 | Go to Step 8 | ||||||
8 |
Warning: Refer to Moving Parts and Hot Surfaces Warning in the Preface section. Using a stethoscope, listen to the A/C compressor for any abnormal noises. Is the compressor causing an abnormal noise? | Go to Step 15 | Go to Step 10 | ||||||
9 | Does a moaning noise exist when the A/C clutch is engaged? | Go to Step 10 | Go to Step 12 | ||||||
10 | Listen to the A/C compressor components and mounting for noise concerns using a stethoscope. Are any of these components loose, damaged or excessively worn? | Go to Step 20 | Go to Step 11 | ||||||
11 |
Are any of the A/C components grounding out and causing a vibration noise? | Go to Step 22 | Go to Step 13 | ||||||
12 | Does a vibration or rattle noise exist when the A/C clutch is engaged? | Go to Step 13 | Go to Step 14 | ||||||
13 | Does the noise stop when the A/C clutch is disengaged? | Go to Step 15 | Go to Step 24 | ||||||
14 |
Do any of the A/C components cause an abnormal noise? | Go to Step 21 | Go to Step 24 | ||||||
15 | Verify that the A/C system is properly charged. Refer to Refrigerant System Capacities. Is the A/C system properly charged? | Go to Step 24 | Go to Step 16 | ||||||
16 | Recharge the A/C system to specification. Refer to Refrigerant Recovery and Recharging. Is the abnormal compressor noise still present? | Go to Step 23 | Go to Step 25 | ||||||
17 | Repair the oil leak. Refer to the appropriate repair procedure for the 4.6L engine. Is the repair complete? | Go to Step 25 | -- | ||||||
18 | Replace the drive belt. Refer to Drive Belt Replacement for the 4.6L engine or Drive Belt Replacement for the 3.9L engine. Is the repair complete? | Go to Step 25 | -- | ||||||
19 | Replace the drive belt tensioner. Refer to Drive Belt Tensioner Replacement for the 4.6L engine Drive Belt Tensioner Replacement for the 3.9L engine. Is the repair complete? | Go to Step 25 | -- | ||||||
20 | Repair or replace the A/C compressor mounting component. Is the repair complete? | Go to Step 25 | -- | ||||||
21 | Repair or replace the component which is causing the moaning concern as needed. Is the repair complete? | Go to Step 25 | -- | ||||||
22 | Correctly route or insulate the A/C component. Is the repair complete? | Go to Step 25 | -- | ||||||
23 | Replace the A/C compressor. Refer to Air Conditioning Compressor Replacement. Is the repair complete? | Go to Step 25 | -- | ||||||
24 | The concern may be caused by an engine related component. Refer to Vibration Analysis - Engine. Did you find and correct the condition? | Go to Step 25 | -- | ||||||
25 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 | ||||||
