In the event of the ABS control unit detecting a fault in the ABS electronic management system, it activates the specific
fault warning indicator on the instrument panel and restores conventional braking functionality without ABS.
The operation of the system is based on the values read for the front and rear wheel speeds; take great care not to damage
the phonic wheels and relative speed sensors when removing the wheels or when working close to these components; the phonic
wheels damage may compromise the operation of the system and cause dangerous malfunctions.
The diagnostic function of the ABS 8M ascertains the functionality of the main system components via hardware/software tests,
but cannot modify the operating parameters of the ABS system.
The DDS diagnostic instrument is connected by cable to the ABS control unit communication socket (A), located beneath the
seat. The connection cable between the tester and the ABS control unit has another branch with a negative and a positive clamp
that must be connected to the vehicle battery to power the tester itself and enable communication with the ABS control unit.
From the SELF-DIAGNOSIS menu of the DDS instrument, select the ABS system model and wait until the correct configuration loads
for analysing the configuration of the vehicle. After switching the vehicle to key-on state, the tester communicates with
the ABS control unit.
Once in this configuration, a number of parameters and states of the ABS control unit and information concerning the control
unit itself may be selected and displayed. If the tester receives notification from the ABS control unit that there are diagnostic
errors dating from a prior test session or current test session still stored in its memory, the user is warned by specific
message on the display and an audible alarm.
The ABS control unit identification number, identified by the prefix ID ECU, may be viewed from the INFO menu.
Select the function “View errors”
This tester function provides the user with information concerning the error list in the ABS control unit memory, indicating
if errors are stored or current. The following codes are given after a short description of the diagnosis type: MEM, indicating
that the error has been stored previously by the ABS control unit but has not been detected in the current test session. ATT,
indicating that the error is current and has been detected during the current test session.
While ATT indicates that the error has been found during the current test session, it does not necessarily indicate that the
error is actually active at the time of indication. For example: disconnecting the front wheel speed sensor causes the code
ATT to be displayed after the error description, but the code continues to be displayed even once the cause of its activation
has been eliminated by reconnecting the sensor, as the ABS will only check sensor operation again after the next key-off/key-on
cycle. As a result, always perform a key-on/key-off cycle after any work on the ABS system, interrupting and re-establishing
communication between the diagnostic instrument and the ABS control unit before checking the updated ABS error list again.
Select the function “ABS system information”
This tester function displays the identification data for the ABS system, such as Supplier reference, Software version and
BARCODE.
Bar Code Data: HQOJM98200RA