Diagnostic information
If the drive belt has repeatedly slipped off the pulley, it may be caused by pulley misalignment.
Additional load that is rapidly applied or released by the accessory drive can also cause the drive belt to slip. Verify that the accessory drive components are operating properly.
If the drive belt is not the correct length, the tensioner may not be able to create the required belt tension.
Description of the test
The numbers below refer to the operations in the diagnostic table:
2. This inspection is performed to check the condition of the drive belt. If the drive belt has slipped, it may have been damaged. Inspect the belt for cuts, tears, damaged belt layers, or missing rib sections.
4. Misalignment of accessory drive pulleys may be caused by improper installation of the pulley or accessory drive component, or the pulley may have been bent during a previous repair. Check the alignment of the pulleys by placing a straight edge in the grooves of two or three pulleys. If a misaligned pulley is found, check the installation and removal procedures for that accessory drive pulley.
5. Inspection of the accessory drive pulley shall include inspection for kinks, dents or other damage that would prevent the drive belt from properly engaging the pulley grooves or that would prevent it from contacting a smooth surface when the back side of the drive belt is used to drive the pulley.
6. Ancillary drive component brackets that are bent or cracked can also cause the drive belt to slip.
7. Inspecting the fasteners will help eliminate the possibility of an improperly installed bolt, nut, gasket or washer. Missing, loose or improper fasteners can prevent the pulley from aligning with the accessory drive bracket when operating under load. Overtightening the fasteners can cause the accessory component bracket to become misaligned.
| Step | Operation | Values | Yes | No |
| 1 |
Have you reviewed the diagnostic information Symptoms - Engine Mechanical and performed the necessary inspections?
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-
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Jump to operations 2
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Go to item Symptoms - Engine Mechanical
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| 2 |
Inspect the drive belt for damage.
Was any damage found to the drive belt?
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-
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Jump to operations 3
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Jump to operations 4
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| 3 |
Install a new drive belt. See. Section 1C1, Engine Mechanical - FAM II 2.4D.
Does the drive belt continue to slip?
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-
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Jump to operations 4
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The system is normal
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| 4 |
Check the alignment of the accessory drive pulley.
Has the problem been detected and corrected?
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-
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Jump to operations 12
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Jump to operations 5
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| 5 |
Inspect the accessory drive pulley for bends or dents.
Has the problem been detected and corrected?
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-
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Jump to operations 12
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Jump to operations 6
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| 6 |
Inspect the accessory drive bracket for cracks or bends.
Has the problem been detected and corrected?
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-
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Jump to operations 12
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Jump to operations 7
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| 7 |
Inspect for proper installation, looseness and/or missing fasteners.
Were any improperly installed, loose and/or missing fasteners found?
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-
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Jump to operations 8
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Jump to operations 9
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| 8 |
Does the drive belt continue to slip?
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-
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Jump to operations 9
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The system is normal
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| 9 |
Check the drive belt tensioner for proper operation. See Drive Belt Tensioner Diagnosis.
Is the drive belt tensioner working properly?
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-
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Jump to operations 11
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Jump to operations 10
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| 10 |
Replace the drive belt tensioner. See Replacing the Drive Belt Tensioner.
Does the drive belt continue to slip?
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-
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Jump to operations 11
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The system is normal
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| 11 |
Check the condition of the drive belt tension roller bearings and/or tensioner pulley.
Has the problem been detected and corrected?
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-
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Jump to operations 12
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-
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| 12 |
Start the engine to check the repair results.
Is the drive belt still slipping?
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-
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-
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The system is normal
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