|
Step
|
Action
|
Yes
|
No
|
1
|
Were you sent here from Symptoms or another diagnostic table?
|
Go to
Step 2
|
Go to
Symptoms - HVAC Systems - Automatic
|
2
|
|
1.
|
A/C system noises can be generally categorized into 3 areas:
|
|
|
•
|
Screeching, squealing, chirping noises
|
|
|
•
|
Vibration/rattle noises
|
|
3.
|
Ensure that the A/C is ON.
|
Is a screeching, squealing noise heard when the A/C is ON?
|
Go to
Step 3
|
Go to
Step 6
|
3
|
With the engine OFF, inspect the drive belt for excessive wear. Refer to
Drive Belt Falls Off and Excessive Wear Diagnosis
.
Is the drive belt excessively worn?
|
Go to
Step 14
|
Go to
Step 4
|
4
|
Inspect the drive belt tension. Refer to
Drive Belt Tensioner Diagnosis
.
Is the drive belt tension correct?
|
Go to
Step 15
|
Go to
Step 5
|
5
|
Inspect the drive belt for excessive oil coverage.
Is the drive belt covered with oil?
|
Go to
Step 13
|
Go to
Step 6
|
6
|
|
2.
|
Ensure that the A/C is ON.
|
Is the compressor locked up?
|
Go to
Step 19
|
Go to
Step 7
|
7
|
Using a stethoscope, listen to the A/C compressor for any abnormal noises.
Is the compressor causing an abnormal noise?
|
Go to
Step 11
|
Go to
Step 8
|
8
|
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 16
|
Go to
Step 9
|
9
|
|
3.
|
Using a stethoscope, move around the entire refrigerant plumbing system, inspecting for any abnormal noises caused by component ground-out.
|
Are any of the A/C components grounding out and causing a noise?
|
Go to
Step 21
|
Go to
Step 10
|
10
|
|
1.
|
1. Idle the engine in PARK with the A/C on.
|
|
2.
|
2. Using a stethoscope, move around the entire A/C system testing for any abnormal noises caused by a component.
|
Do any of the A/C components cause an abnormal noise?
|
Go to
Step 17
|
Go to
Step 20
|
11
|
Verify that the A/C system is properly charged. Refer to
Refrigerant System Specifications
.
Is the A/C system properly charged?
|
Go to
Step 19
|
Go to
Step 16
|
12
|
Recharge the A/C system to specification. Refer to
Refrigerant Recovery and Recharging (Belt Driven Compressor)
.
Is the abnormal compressor noise still present?
|
Go to
Step 20
|
Go to
Step 21
|
13
|
Repair the oil leak. Refer to the appropriate repair procedure in Engine Mechanical.
Is the repair complete?
|
Go to
Step 21
|
-
|
14
|
Replace the drive belt. Refer to
Drive Belt Replacement
.
Is the replacement complete?
|
Go to
Step 21
|
-
|
15
|
Replace the drive belt tensioner. Refer to
Drive Belt Replacement
.
Is the replacement complete?
|
Go to
Step 21
|
-
|
16
|
Repair or replace the A/C compressor mounting component.
Is the repair complete?
|
Go to
Step 21
|
-
|
17
|
Repair or replace the component which is causing the moaning concern as needed.
Is the repair complete?
|
Go to
Step 21
|
-
|
18
|
Correctly route or insulate the A/C component.
Is the repair complete?
|
Go to
Step 21
|
-
|
19
|
Replace the A/C compressor. Refer to
A/C compressor, replacement (LF1)
A/C compressor, replacement (LAU)
.
Is the replacement complete?
|
Go to
Step 21
|
-
|
20
|
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 21
|
-
|
21
|
Operate the system in order to verify the repair.
Did you find and correct the condition?
|
System OK
|
Go to
Step 2
|
