| | Results of the tests |
| 0 | PRELIMINARY CHECKS | All OK | Problems met | Operation |
|---|
| Resting
the foot on the brake pedal, check that the pedal sinks when the
engine is started, because of the vacuum in the braking circuit | Continue to Step 1 | Absence of or partial
servo assistance | Continue to Step 1 |
| 1 | CHECK ON VACUUM PIPE | All OK | Problems met | Operation |
|---|
| Check
vacuum pipe: must not be bent or damaged | Continue to Step 2 | Pipe bent | Restore the correct geometry |
| Pipe damaged | Replace the damaged pipe Op. 3330D26 |
| 2 | CHECK NON-RETURN VALVE | All OK | Problems met | Operation |
|---|
| Check
that the non-return valve is working properly | Continue to Step 3 | Faulty operation | Replace check valve Op. 3330D26 |
| 3 | CHECK BRAKE SERVO | All OK | Problems met | Operation |
|---|
| Check in particular: - that there are no air leaks
- that there is no seizing or sticking
| Continue to Step 4 | Brake servo with leaks | Replace the brake servo/pump
assembly Op. 3330D02 |
| Brake servo operation is jerky | Replace the brake servo/pump assembly Op. 3330D02 |
| 4 | CHECK ON VACUUM | All OK | Problems met | Operation |
|---|
| Check
the vacuum level in the servo brake system | Under particular conditions of
use, low engine rpm with excessive use of the brakes, the vacuum
for operating the servo brake may be insufficient resulting in hardening
of the brake pedal. It is pointless replacing the servo unit. |
| Continue to Step 5 | Value incorrect | Eliminate blockages in the
manifold |
| Value correct | Replace the brake servo/pump assembly Op. 3330D02 |
| 5 | CHECKING PUMP | All OK | Problems met | Operation |
|---|
| Check
that the brake pump has not seizedCheck that one or more wheels do not remain braked | Continue to Step 6 | Seizure of the pump | Replace the brake servo/pump
assembly Op. 3330D02 |
| Seizure of a front caliper | Replace the caliper Op. 3310A30 |
| Seizure of a rear caliper | Replace the caliper Op. 3310B36 |
| The car remains braked | Remove the servo/pump assembly Op. 3330D02 and
adjust the projection of the pushrod |
| The car remains braked at the rear | Repair the handbrake |
| 6 | CHECK ON CORRECT OPERATION | All OK | Problems met | Operation |
|---|
| Test
the vehicle before delivery to the customer, to check that the fault
is no longer present. | The test is essential, as the braking system involves a safety
feature of the car |
| | Fault persists | Search for the
fault starting from another symptom' |