Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the HVAC Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - HVAC Systems - Automatic in HVAC Systems - Automatic or Symptoms - HVAC Systems - Manual in HVAC Systems - Manual | ||||||
2 |
Is an abnormal noise present? | Go to Step 3 | |||||||
3 |
Is the A/C clutch engaged and supplying cold air to the passenger compartment? | Go to Step 4 | Go to HVAC Compressor Clutch Does Not Engage in HVAC Systems - Automatic or HVAC Compressor Clutch Does Not Engage in HVAC Systems - Manual | ||||||
4 | A/C system noises can be generally categorized into three areas:
Is a screech/squealing noise heard when the A/C clutch is engaged? | Go to Step 5 | Go to Step 11 | ||||||
5 | Inspect the A/C compressor drive belt for excessive wear or oil coverage. Is the drive belt excessively worn or covered with oil? | Go to Step 6 | Go to Step 7 | ||||||
6 |
Did you complete the repair? | Go to Step 25 | -- | ||||||
7 | Is the A/C compressor clutch slipping or the compressor locked up? | Go to Step 8 | Go to Step 9 | ||||||
8 |
Did you complete the repair? | Go to Step 25 | -- | ||||||
9 |
Is the idler pulley and tensioner causing an abnormal noise? | Go to Step 10 | Go to Step 11 | ||||||
10 | Replace the A/C compressor drive belt idler pulley or tensioner as necessary. Did you complete the repair? | Go to Step 25 | -- | ||||||
11 | Does a moaning noise exist when the A/C clutch is engaged? | Go to Step 12 | Go to Step 20 | ||||||
12 |
Important: A moaning/rumbling noise originating from the compressor could be caused by the system being less than 236 ml (8 oz) low on charge. The performance test may not detect the system being under charged less than 236 ml (8 oz). Perform a system performance test to verify the A/C system is properly charged. Refer to Air Conditioning (A/C) System Performance Test . Is the A/C system properly charged? | Go to Step 14 | Go to Step 13 | ||||||
13 |
Does the moaning noise exist when the A/C clutch is engaged? | Go to Step 14 | Go to Step 25 | ||||||
14 | Inspect the A/C compressor mounting, idler pulley, and tensioner for concerns using a stethoscope. Are any of these components loose, damaged or excessively worn? | Go to Step 15 | Go to Step 16 | ||||||
15 | Repair or replace the A/C compressor mounting, idler pulley or tensioner/tensioner pulley as needed. Did you complete the repair? | Go to Step 25 | -- | ||||||
16 |
Are any of the A/C components grounding out and causing a noise? | Go to Step 17 | Go to Step 18 | ||||||
17 | Repair or replace the component which is causing the moaning concern as needed. Did you complete the repair? | Go to Step 25 | -- | ||||||
18 | Does the concern go away with the A/C clutch disengaged and the engine idling in PARK? | Go to Step 19 | Go to Vibration Analysis - Engine in Vibration Diagnosis and Correction | ||||||
19 | Replace the A/C Compressor. Refer to Air Conditioning Compressor Replacement . Did you complete the repair? | Go to Step 25 | -- | ||||||
20 | Does a vibration or rattle noise exist when the A/C clutch is engaged? | Go to Step 21 | System OK | ||||||
21 | Inspect the A/C compressor mounting, idler pulley, and tensioner for concerns using a stethoscope. Are any of these components loose, damaged or excessively worn? | Go to Step 15 | Go to Step 22 | ||||||
22 |
Are any of the A/C components causing an abnormal noise? | Go to Step 23 | Go to Step 24 | ||||||
23 | Repair or replace the component which is causing the vibration/rattle concern as needed. Did you complete the repair? | Go to Step 25 | -- | ||||||
24 | Is the vibration/rattle coming from the A/C compressor internally? | Go to Step 19 | Go to Vibration Analysis - Engine in Vibration Diagnosis and Correction | ||||||
25 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |