|  |  | Test results | 
| 0 | PRELIMINARY CHECKS | All OK | Problems encountered | Operation | 
|---|
|  | Adjust the backrest by pressing with your hands to identify the sources of the noise coming from the backrest | Move on to Step 1 | Components with interference | Move the interfering components apart and, if the welding is insufficient, renew it | 
| 1 | CHECK ON MATCHING OF UPPER AND LOWER CROSSMEMBERS WITH BACKREST SIDES | All OK | Problems encountered | Operation | 
|---|
|  | Check the areas where the upper and lower crossmembers are matched with the backrest sides | Move on to Step 2 | Breaks in the matching areas | Replace the backrest assembly    Op. 7045A18  FRONT SEAT BACKREST ASSEMBLY (ONE), LEFT OR RIGHT - R.R. | 
| 2 | CHECK ON SPRING PLATE FASTENING | All OK | Problems encountered | Operation | 
|---|
|  | Check that the spring plate rivets are correctly fastened to the retaining borders.Also check for any broken springs | Move on to Step 3 | 1. Rivets detached/loose2. Springs broken | 1. Renew the spring fastening rivets and/or reattach the retaining border2. Replacement of backrest springs assembly | 
| 3 | CREAKING CHECK | All OK | Problems encountered | Operation | 
|---|
|  | Check on creaking caused by whiplash mechanism on backrest | Move on to Step 4 | 1. Joint springs creaking2. Contacts with backrest internal components (frame, etc.) | 1. Lubricate springs/joints with molybdenum disulphide grease2. Space out the parts in contact | 
| 4 | CHECK ON CORRECT OPERATION | All OK | Problems encountered | Operation | 
|---|
|  | Check that the fault is no longer present | End of diagnosis | The fault persists | Replace the seat frame    Op. 7045A86 FRONT SEAT FRAME (ONE), LEFT OR RIGHT, R.R. |