|  |  | Results of the tests | 
| 0 | PRELIMINARY CHECKS | All OK | Problems met | Operation | 
|---|
|  | Check
operation of central locking | Continue to Step 
                              1 | Central door locking not working
either | See
table 
                                 P10 | 
| 1 |  | All OK | Problems met | Operation | 
|---|
|  | Check:: (
                               See   E4020  REV COUNTER INSTRUMENT 
                              ).service fuseignition-operated service fusesupply to check instrumentearth for check instrumentconnections between check and lock switchesconnection between check and boot switchearth for lock switches
 | Continue to Step 
                              2 | Component defective | Replace the component involved
(if a fuse is involved, search for the cause of the problem) | 
| Connections broken | Restore connections | 
| 2 | CHECK LOCK SWITCHES | All OK | Problems met | Operation | 
|---|
|  | Check
that the door lock switches are working | Continue to Step 
                              3 | Fault in front door switches | Check and if necessary replace
the door lock motors 
                               Op.   7005N21 | 
| Fault in rear door switches | Check and if necessary replace the door lock motors
                               Op.   7010N21 | 
| Central door locking not working either | See table 
                                 P10 | 
| 3 | CHECK ON CHECK INSTRUMENT | All OK | Problems met | Operation | 
|---|
|  | Check
the operation of the check instrument 
                               see DESCRIPTION AND OPERATION: 5560 INSTRUMENT PANEL | Continue to Step 
                              4 | Instrument not working | Replace check instrument 
                               Op.   5560C60 | 
| 4 | CHECKING CORRECT OPERATION | All OK | Problems met | Operation | 
|---|
|  | Check
that the fault is no longer present | End of diagnosis | Fault persists | Search for the
fault starting from another symptom' | 
|  |  | Results of the tests | 
| 0 | PRELIMINARY CHECK | All OK | Problems met | Operation | 
|---|
|  | Check
that the courtesy light works when the door switches are operated. | Continue to Step 
                              2 | Fault in courtesy light | Continue to Step 
                               1 | 
| 1 | CHECKING CONTINUITY | All OK | Problems met | Operation | 
|---|
|  | Check
the correct electrical connection of the switches on doors between
earth point and dashboard / Infocenter junction.
                              If the warning is issued when only one door is opened, check
the individual electrical branch. 
                               See   E4024  INFOCENTER INSTRUMENT | Continue to Step 
                              2 | Connections not correct. | Renew the electrical connection. | 
| Switch positioned incorrectly or faulty. | Renew or replace the door switch. | 
| 2 | CHECK THE CORRECT INSTRUMENT OPERATION | All OK | Problems met | Operation | 
|---|
|  | Check
the correct operation of the door open indicator on the Infocenter | Continue to Step 
                              3 | Infocenter faulty | Replace Infocenter. | 
| 3 | CHECKING CORRECT OPERATION | All OK | Problems met | Operation | 
|---|
|  | Check
that the fault is no longer present | End of diagnosis | Fault persists | Search for the
fault starting from another symptom' |